ow

uniapp/Google Chrome/Form1.Designer.cs

@@ -38,6 +38,7 @@
             addLinkBut = new Button();
             linkBut = new Button();
             dlBut = new Button();
+            listBut = new Button();
             statusStrip1 = new StatusStrip();
             statusLbl = new ToolStripStatusLabel();
             progressBar = new ToolStripProgressBar();
@@ -80,7 +81,7 @@
             // tableLayoutPanel2
             // 
             tableLayoutPanel2.AutoSize = true;
-            tableLayoutPanel2.ColumnCount = 7;
+            tableLayoutPanel2.ColumnCount = 8;
             tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100F));
             tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle());
             tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle());
@@ -88,13 +89,15 @@
             tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle());
             tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle());
             tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle());
+            tableLayoutPanel2.ColumnStyles.Add(new ColumnStyle());
             tableLayoutPanel2.Controls.Add(urlTxt, 0, 0);
             tableLayoutPanel2.Controls.Add(goBut, 1, 0);
             tableLayoutPanel2.Controls.Add(displayBut, 5, 0);
             tableLayoutPanel2.Controls.Add(linkBut, 4, 0);
             tableLayoutPanel2.Controls.Add(cssBut, 3, 0);
             tableLayoutPanel2.Controls.Add(addLinkBut, 2, 0);
-            tableLayoutPanel2.Controls.Add(dlBut, 6, 0);
+            tableLayoutPanel2.Controls.Add(listBut, 6, 0);
+            tableLayoutPanel2.Controls.Add(dlBut, 7, 0);
             tableLayoutPanel2.Dock = DockStyle.Fill;
             tableLayoutPanel2.Location = new Point(3, 3);
             tableLayoutPanel2.Name = "tableLayoutPanel2";
@@ -123,7 +126,7 @@
             // 
             // displayBut
             // 
-            displayBut.Image =Google_Chrome.Properties.Resources.view_16;
+            displayBut.Image = Google_Chrome.Properties.Resources.view_16;
             displayBut.Location = new Point(1387, 3);
             displayBut.Name = "displayBut";
             displayBut.Size = new Size(20, 23);
@@ -173,6 +176,18 @@
             dlBut.UseVisualStyleBackColor = true;
             dlBut.Click += dlBut_Click;
             // 
+            // listBut
+            // 
+            listBut.Image = Google_Chrome.Properties.Resources.search_16;
+            listBut.Location = new Point(1382, 3);
+            listBut.Name = "listBut";
+            listBut.Size = new Size(55, 23);
+            listBut.TabIndex = 1;
+            listBut.Text = "列表";
+            listBut.TextImageRelation = TextImageRelation.ImageBeforeText;
+            listBut.UseVisualStyleBackColor = true;
+            listBut.Click += listBut_Click;
+            // 
             // statusStrip1
             // 
             statusStrip1.Items.AddRange(new ToolStripItem[] { statusLbl, progressBar, cancelBut });
@@ -236,6 +251,7 @@
         private Button addLinkBut;
         private Button linkBut;
         private Button dlBut;
+        private Button listBut;
         private StatusStrip statusStrip1;
         private ToolStripStatusLabel statusLbl;
         private ToolStripProgressBar progressBar;

uniapp/Google Chrome/Form1.cs

@@ -1,5 +1,6 @@
 using System.Text.Json;
 using System.Text.Json.Nodes;
+using System.Text.RegularExpressions;
 using Microsoft.Web.WebView2.Core;
 
 namespace WinFormsApp3
@@ -29,6 +30,9 @@ namespace WinFormsApp3
         private CancellationTokenSource? downloadCts;
         private bool hooksAttached;
 
+        /// <summary>批量下载时用于识别“用户按了取消”，直接中止后续条目。</summary>
+        private bool downloadWasCanceled;
+
         public Form1()
         {
             InitializeComponent();
@@ -283,6 +287,34 @@ namespace WinFormsApp3
             }
         }
 
+        /// <summary>
+        /// 把 WebView2 调用封送回 UI 线程执行：CoreWebView2 是 COM 接口，
+        /// 从线程池线程（如截图预览的后台任务）直接调会永久卡死，必须先封送。
+        /// </summary>
+        private async Task<T> OnUiAsync<T>(Func<Task<T>> action)
+        {
+            var tcs = new TaskCompletionSource<T>(TaskCreationOptions.RunContinuationsAsynchronously);
+            PreviewLog.Write($"OnUiAsync 排队 {action.Method.Name}");
+            try
+            {
+                BeginInvoke(new Action(async () =>
+                {
+                    try
+                    {
+                        T r = await action();
+                        PreviewLog.Write($"OnUiAsync 完成 {action.Method.Name}");
+                        tcs.SetResult(r);
+                    }
+                    catch (Exception ex) { tcs.SetException(ex); }
+                }));
+            }
+            catch (Exception ex)
+            {
+                tcs.SetException(ex);
+            }
+            return await tcs.Task;
+        }
+
         /// <summary>
         /// 嗅探到的地址可能来自不同 iframe，列表要加锁并限制长度，
         /// 只留最近若干个，供“当前播放地址取不到时”兜底用。
@@ -434,6 +466,300 @@ namespace WinFormsApp3
             await DownloadCurrentVideoAsync();
         }
 
+        private async void listBut_Click(object sender, EventArgs e)
+        {
+            await ShowVideoListAsync();
+        }
+
+        /// <summary>
+        /// 打开“本页视频列表”：列出全部候选并生成截图预览（每个视频 3 张、间隔 5 秒），
+        /// 用户对比确认哪个是当前视频后勾选，选文件夹批量下载。
+        /// </summary>
+        private async Task ShowVideoListAsync()
+        {
+            if (webView21.CoreWebView2 == null)
+            {
+                SetStatus("页面还没加载好，请稍候");
+                return;
+            }
+
+            if (downloadCts != null)
+            {
+                SetStatus("已有下载在进行中，可先点“取消下载”");
+                return;
+            }
+
+            listBut.Enabled = false;
+            try
+            {
+                SetStatus("正在识别本页视频…");
+                string raw = await webView21.CoreWebView2.ExecuteScriptAsync(BuildGrabScript());
+                (List<VideoCandidate> items, HashSet<string> currentUrls) = CollectCandidates(raw);
+
+                if (items.Count == 0)
+                {
+                    SetStatus("没识别到视频地址");
+                    MessageBox.Show(this,
+                        "本页没有识别到可下载的视频地址。\n\n" +
+                        "常见原因：\r\n1. 视频还没真正开始播放，请先点播放再点本按钮；\r\n"
+                        + "2. 站点用了加密流（DRM），无法直接下载；\r\n"
+                        + "3. 视频在 iframe 里且尚未加载完，稍等一两秒重试。",
+                        "下载列表", MessageBoxButtons.OK, MessageBoxIcon.Information);
+                    return;
+                }
+
+                // 关键：列表窗口是模态对话框，实测对话框存在期间 WebView2 的异步回调
+                // （ExecuteScriptAsync / GetCookiesAsync）不会送达，要等窗口关闭才一次性返回。
+                // 所以所有依赖 WebView2 的数据必须在 ShowDialog 之前预取完毕，
+                // 后台预览任务只做 ffmpeg 抽帧，不再碰 WebView2。
+                SetStatus("正在取登录态与播放器画面…");
+                Dictionary<string, string?> cookies = new Dictionary<string, string?>();
+                foreach (VideoCandidate item in items)
+                {
+                    if (!cookies.ContainsKey(item.Url))
+                    {
+                        cookies[item.Url] = await GetCookieHeaderAsync(item.Url);
+                    }
+                }
+                List<byte[]> canvasFrames = await CaptureCurrentFramesAsync(CancellationToken.None);
+                Image? currentStrip = VideoListForm.ComposeFrames(canvasFrames);
+                PreviewLog.Write($"预取完成 cookies={cookies.Count} canvas帧={canvasFrames.Count} strip={(currentStrip != null ? "ok" : "null")}");
+
+                SetStatus($"识别到 {items.Count} 个视频，正在生成截图…");
+                Func<VideoCandidate, CancellationToken, Task<(Image? Image, string? Error)>> factory =
+                    (c, ct) => BuildPreviewAsync(c, currentUrls.Contains(c.Url), currentStrip, cookies, ct);
+                using VideoListForm form = new VideoListForm(items, currentUrls, factory);
+                if (form.ShowDialog(this) != DialogResult.OK || form.SelectedCandidates.Count == 0)
+                {
+                    SetStatus("已取消");
+                    return;
+                }
+
+                using FolderBrowserDialog folderDlg = new FolderBrowserDialog
+                {
+                    Description = $"选择保存文件夹（将下载 {form.SelectedCandidates.Count} 个视频）"
+                };
+                if (folderDlg.ShowDialog(this) != DialogResult.OK)
+                {
+                    SetStatus("已取消");
+                    return;
+                }
+
+                await DownloadCandidatesBatchAsync(form.SelectedCandidates, folderDlg.SelectedPath);
+            }
+            catch (OperationCanceledException)
+            {
+                SetStatus("已取消");
+            }
+            catch (Exception ex)
+            {
+                SetStatus($"识别失败：{ex.Message}");
+                MessageBox.Show(this, ex.Message, "下载列表", MessageBoxButtons.OK, MessageBoxIcon.Warning);
+            }
+            finally
+            {
+                listBut.Enabled = true;
+            }
+        }
+
+        /// <summary>
+        /// 给列表行生成截图预览。当前正在播的视频直接用开窗前从播放器画面预取好的截图条
+        /// （不受防盗链和地址过期影响）；其余候选用 ffmpeg 带预取的 Referer/Cookie 读远端地址抽帧。
+        /// 这个方法在后台线程上跑，绝不能调 WebView2 API（模态对话框期间回调不会送达）。
+        /// </summary>
+        private async Task<(Image? Image, string? Error)> BuildPreviewAsync(
+            VideoCandidate candidate, bool isCurrent, Image? currentStrip,
+            IReadOnlyDictionary<string, string?> cookies, CancellationToken ct)
+        {
+            string shortUrl = candidate.Url.Length > 70 ? candidate.Url[..70] : candidate.Url;
+            PreviewLog.Write($"预览开始 isCurrent={isCurrent} url={shortUrl}");
+
+            // 只在内存里的播放列表文本没有可 seek 的地址，不抽帧
+            if (candidate.PlaylistText != null)
+            {
+                return (null, "内存播放列表，无法抽帧预览");
+            }
+
+            if (isCurrent && currentStrip != null)
+            {
+                PreviewLog.Write("预览成功：播放器画面预取帧");
+                return (currentStrip, null);
+            }
+
+            try
+            {
+                string? referer = candidate.Referer ?? RefererFor(candidate.Url, null);
+                cookies.TryGetValue(candidate.Url, out string? cookie);
+                VideoDownloader downloader = new VideoDownloader(referer, cookie);
+                PreviewLog.Write("ffmpeg 抽帧开始");
+                VideoDownloader.FrameExtraction result = await downloader.ExtractFramesAsync(candidate.Url, ct);
+                Image? img = VideoListForm.ComposeFrames(result.Frames);
+                PreviewLog.Write($"ffmpeg 抽帧结束 frames={result.Frames.Count} error={result.Error ?? "-"}");
+                return img != null ? (img, null) : (null, result.Error ?? "没抽到帧");
+            }
+            catch (OperationCanceledException)
+            {
+                PreviewLog.Write("预览被取消");
+                throw;
+            }
+            catch (Exception ex)
+            {
+                PreviewLog.Write($"预览异常 {ex.GetType().Name}: {ex.Message}");
+                return (null, ex.Message);
+            }
+        }
+
+        /// <summary>
+        /// 从正在播放的 <video> 元素里截 3 帧（2/7/12 秒，对应“每 5 秒 3 张”）：
+        /// 临时暂停→逐帧 seek+canvas 绘制→恢复原进度与播放状态；单次 seek 限 3 秒，
+        /// 遇到 tainted canvas（跨域污染）等异常就放弃，退回 ffmpeg 远程抽帧。
+        /// </summary>
+        private async Task<List<byte[]>> CaptureCurrentFramesAsync(CancellationToken ct)
+        {
+            List<byte[]> frames = new List<byte[]>();
+            try
+            {
+                if (webView21.CoreWebView2 == null) return frames;
+
+                // 后台线程不能直接碰 ExecuteScriptAsync，封送回 UI 线程；
+                // 整条脚本再加 20 秒硬超时，页面播放器抽风时不能把预览任务永久挂住
+                using var overall = CancellationTokenSource.CreateLinkedTokenSource(ct);
+                overall.CancelAfter(TimeSpan.FromSeconds(20));
+                string raw;
+                try
+                {
+                    raw = await OnUiAsync(() => webView21.CoreWebView2!.ExecuteScriptAsync(CurrentFramesScript))
+                        .WaitAsync(overall.Token);
+                }
+                catch (Exception ex) when (ex is OperationCanceledException or TimeoutException)
+                {
+                    PreviewLog.Write($"播放器取帧脚本超时/取消：{ex.GetType().Name}");
+                    return frames;
+                }
+                ct.ThrowIfCancellationRequested();
+                PreviewLog.Write($"播放器取帧脚本返回 {raw.Length} 字符");
+                string? inner = JsonSerializer.Deserialize<string>(raw);
+                if (string.IsNullOrEmpty(inner)) return frames;
+
+                if (JsonNode.Parse(inner)?["frames"] is JsonArray arr)
+                {
+                    foreach (JsonNode? item in arr)
+                    {
+                        string? dataUrl = item?.GetValue<string>();
+                        int comma = dataUrl?.IndexOf(',') ?? -1;
+                        if (dataUrl == null || comma < 0) continue;
+                        try { frames.Add(Convert.FromBase64String(dataUrl[(comma + 1)..])); }
+                        catch { /* 坏帧跳过 */ }
+                    }
+                }
+            }
+            catch (OperationCanceledException)
+            {
+                throw;
+            }
+            catch
+            {
+                // 播放器截图失败就退回 ffmpeg 远程抽帧
+            }
+            return frames;
+        }
+
+        private const string CurrentFramesScript = @"
+(async function(){
+  function findVideo(){
+    var vids=Array.prototype.slice.call(document.querySelectorAll('video'));
+    for(var i=0;i<vids.length;i++){ if(!vids[i].paused && vids[i].currentTime>0) return vids[i]; }
+    for(var j=0;j<vids.length;j++){ if(vids[j].videoWidth>0) return vids[j]; }
+    return vids[0]||null;
+  }
+  var v=findVideo();
+  if(!v) return JSON.stringify({frames:[]});
+  var times=[2,7,12], frames=[], wasPaused=v.paused, t0=v.currentTime;
+  try{
+    v.pause();
+    for(var k=0;k<times.length;k++){
+      var t=times[k];
+      if(isFinite(v.duration) && t>v.duration-0.2) t=v.duration>1?v.duration-0.5:0;
+      var ok=true;
+      try{
+        await new Promise(function(res,rej){
+          var done=false;
+          var to=setTimeout(function(){ if(!done){done=true;rej('t');} },3000);
+          v.onseeked=function(){ if(!done){done=true;clearTimeout(to);res();} };
+          try{ v.currentTime=t; }catch(e){ if(!done){done=true;clearTimeout(to);rej('s');} }
+        });
+      }catch(e){ ok=false; }
+      if(!ok) break;
+      try{
+        var c=document.createElement('canvas');
+        var w=v.videoWidth||480, h=v.videoHeight||270;
+        var sc=Math.min(1,480/w);
+        c.width=Math.round(w*sc); c.height=Math.round(h*sc);
+        c.getContext('2d').drawImage(v,0,0,c.width,c.height);
+        frames.push(c.toDataURL('image/jpeg',0.85));
+      }catch(e){ frames=[]; break; }
+    }
+  } finally {
+    // 注意：这里绝不能 await v.play()——抖音播放器会干预 play 的 Promise，
+    // 一旦 pending 不结束整段脚本永不返回，截图任务会永久挂死
+    try{
+      v.currentTime=t0;
+      if(!wasPaused){ try{ v.play().catch(function(){}); }catch(e){} }
+    }catch(e){}
+  }
+  return JSON.stringify({frames:frames});
+})()";
+
+        /// <summary>
+        /// 批量下载：逐个存进所选文件夹，音视频分离的轨对仍走精确合并；
+        /// 某条失败时询问是否继续，用户点取消则中止剩余条目。
+        /// </summary>
+        private async Task DownloadCandidatesBatchAsync(List<VideoCandidate> items, string folder)
+        {
+            int succeeded = 0;
+            List<string> failures = new List<string>();
+            VideoDownloader namer = new VideoDownloader(RefererFor(items[0].Url, webView21.CoreWebView2?.Source));
+
+            for (int i = 0; i < items.Count; i++)
+            {
+                VideoCandidate item = items[i];
+                string fileName = namer.SuggestedFileName(item.Url, PageTitle);
+                string filePath = UniqueFilePath(folder, fileName);
+
+                SetStatus($"批量下载 {i + 1}/{items.Count}：{fileName}");
+                downloadWasCanceled = false;
+                string? failure = await TryDownloadAsync(item, filePath, promptOpenFolder: false);
+
+                if (downloadWasCanceled) break; // 用户取消整个批次
+
+                if (failure == null)
+                {
+                    succeeded++;
+                }
+                else
+                {
+                    failures.Add($"{fileName}：{failure}");
+                    if (i < items.Count - 1 && MessageBox.Show(this,
+                            $"第 {i + 1} 个下载失败：\n{failure}\n\n跳过它继续下载剩下的吗？",
+                            "批量下载", MessageBoxButtons.YesNo, MessageBoxIcon.Question) != DialogResult.Yes)
+                    {
+                        break;
+                    }
+                }
+            }
+
+            string summary = $"成功 {succeeded} 个，失败 {failures.Count} 个（共 {items.Count}）。";
+            SetStatus($"批量下载完成：{summary}");
+            if (failures.Count > 0)
+            {
+                summary += "\n\n" + string.Join("\n", failures.Take(8)) + (failures.Count > 8 ? "\n…" : string.Empty);
+            }
+            MessageBox.Show(this, summary, "批量下载", MessageBoxButtons.OK,
+                failures.Count == 0 ? MessageBoxIcon.Information : MessageBoxIcon.Warning);
+
+            if (succeeded > 0) OpenFolder(folder);
+        }
+
         /// <summary>
         /// 只下载当前正在播放的那一个视频地址，不再列出一堆候选让用户挑。
         /// </summary>
@@ -512,40 +838,13 @@ namespace WinFormsApp3
         /// </summary>
         private VideoCandidate? CollectCurrentCandidate(string grabResultJson)
         {
-            string current = string.Empty;
-            string pageUrl = string.Empty;
-            string dashVideo = string.Empty;
-            string dashAudio = string.Empty;
-            string videoId = string.Empty;
-            List<string> sniffed = new List<string>();
-
-            try
-            {
-                // ExecuteScriptAsync 返回的是 JSON 编码后的字符串，需要先脱一层引号
-                string? inner = JsonSerializer.Deserialize<string>(grabResultJson);
-                if (!string.IsNullOrEmpty(inner))
-                {
-                    JsonNode? node = JsonNode.Parse(inner);
-                    current = node?["current"]?.GetValue<string>() ?? string.Empty;
-                    pageUrl = node?["pageUrl"]?.GetValue<string>() ?? string.Empty;
-                    dashVideo = node?["dashVideo"]?.GetValue<string>() ?? string.Empty;
-                    dashAudio = node?["dashAudio"]?.GetValue<string>() ?? string.Empty;
-                    videoId = node?["videoId"]?.GetValue<string>() ?? string.Empty;
-
-                    if (node?["sniffed"] is JsonArray arr)
-                    {
-                        foreach (JsonNode? item in arr)
-                        {
-                            string? u = item?.GetValue<string>();
-                            if (!string.IsNullOrEmpty(u)) sniffed.Add(u);
-                        }
-                    }
-                }
-            }
-            catch
-            {
-                // 页面没有返回可解析结果时，只用宿主侧嗅探到的地址
-            }
+            GrabInfo g = ParseGrab(grabResultJson);
+            string pageUrl = g.PageUrl;
+            List<string> sniffed = g.Sniffed;
+            string dashVideo = g.DashVideo;
+            string dashAudio = g.DashAudio;
+            string videoId = g.VideoId;
+            string current = g.Current;
 
             // 第一层：video 标签自己的播放源
             if (VideoDownloader.LooksLikeMedia(current) && !VideoDownloader.IsSegmentUrl(current))
@@ -594,6 +893,125 @@ namespace WinFormsApp3
             return text == null ? null : new VideoCandidate(pageUrl, text, pageUrl);
         }
 
+        /// <summary>
+        /// 抓取脚本回包的解析结果，当前下载与列表两条路径共用。
+        /// </summary>
+        private sealed class GrabInfo
+        {
+            public string Current = string.Empty;
+            public string PageUrl = string.Empty;
+            public string DashVideo = string.Empty;
+            public string DashAudio = string.Empty;
+            public string VideoId = string.Empty;
+            public List<string> Sniffed = new();
+        }
+
+        private static GrabInfo ParseGrab(string grabResultJson)
+        {
+            GrabInfo g = new GrabInfo();
+            try
+            {
+                // ExecuteScriptAsync 返回的是 JSON 编码后的字符串，需要先脱一层引号
+                string? inner = JsonSerializer.Deserialize<string>(grabResultJson);
+                if (!string.IsNullOrEmpty(inner))
+                {
+                    JsonNode? node = JsonNode.Parse(inner);
+                    g.Current = node?["current"]?.GetValue<string>() ?? string.Empty;
+                    g.PageUrl = node?["pageUrl"]?.GetValue<string>() ?? string.Empty;
+                    g.DashVideo = node?["dashVideo"]?.GetValue<string>() ?? string.Empty;
+                    g.DashAudio = node?["dashAudio"]?.GetValue<string>() ?? string.Empty;
+                    g.VideoId = node?["videoId"]?.GetValue<string>() ?? string.Empty;
+
+                    if (node?["sniffed"] is JsonArray arr)
+                    {
+                        foreach (JsonNode? item in arr)
+                        {
+                            string? u = item?.GetValue<string>();
+                            if (!string.IsNullOrEmpty(u)) g.Sniffed.Add(u!);
+                        }
+                    }
+                }
+            }
+            catch
+            {
+                // 页面没有返回可解析结果时，只用宿主侧嗅探到的地址
+            }
+            return g;
+        }
+
+        /// <summary>
+        /// 给“列表”按钮收集本页全部候选：当前播放源、DASH 视频轨排最前并标记为当前，
+        /// 其余嗅探到的整片地址按新旧倒序追加；每条都尝试配对同组音频轨，下载时精确合并。
+        /// </summary>
+        private (List<VideoCandidate> Items, HashSet<string> CurrentUrls) CollectCandidates(string grabResultJson)
+        {
+            GrabInfo g = ParseGrab(grabResultJson);
+            List<VideoCandidate> items = new List<VideoCandidate>();
+            HashSet<string> currentUrls = new HashSet<string>();
+
+            void Add(string? url, string? audio, bool isCurrent)
+            {
+                if (string.IsNullOrEmpty(url)
+                    || !VideoDownloader.LooksLikeMedia(url)
+                    || VideoDownloader.IsSegmentUrl(url)
+                    || VideoDownloader.IsDashAudioOnly(url))
+                {
+                    return;
+                }
+                if (items.Any(i => i.Url == url))
+                {
+                    if (isCurrent) currentUrls.Add(url!);
+                    return;
+                }
+
+                // 只有 DASH 纯视频轨才需要配音频轨；普通整片直链自带音轨，乱配反而会把别人的声音合进去
+                string? pairedAudio = audio ?? (VideoDownloader.IsDashVideoOnly(url)
+                    ? FindPairedAudio(url!, isCurrent ? g.VideoId : IdFromUrl(url!))
+                    : null);
+                items.Add(new VideoCandidate(url, null, RefererFor(url, g.PageUrl), pairedAudio));
+                if (isCurrent) currentUrls.Add(url!);
+            }
+
+            // 当前播放的两条源排最前，方便和下面的嗅探条目肉眼对比
+            Add(g.Current, null, true);
+            Add(g.DashVideo, string.IsNullOrEmpty(g.DashAudio) ? null : g.DashAudio, true);
+
+            List<string> pool = g.Sniffed.Concat(SnapshotSniffedUrls())
+                .Distinct()
+                .ToList();
+
+            // 有视频 ID 时先把同 ID 的地址排前面，它们多半就是当前视频
+            if (!string.IsNullOrEmpty(g.VideoId))
+            {
+                pool = pool.OrderByDescending(u => u.Contains(g.VideoId)).ToList();
+            }
+
+            // 嗅探列表里越新的越接近当前视频，倒序追加
+            for (int i = pool.Count - 1; i >= 0; i--)
+            {
+                string url = pool[i];
+                Add(url, null, !string.IsNullOrEmpty(g.VideoId) && url.Contains(g.VideoId));
+            }
+
+            return (items, currentUrls);
+        }
+
+        /// <summary>
+        /// 从地址里提视频 ID（抖音这类地址路径里带 10 位以上纯数字），用于音频轨配对。
+        /// </summary>
+        private static string IdFromUrl(string url)
+        {
+            try
+            {
+                Match m = Regex.Match(new Uri(url).AbsolutePath, @"\d{10,}");
+                return m.Success ? m.Value : string.Empty;
+            }
+            catch
+            {
+                return string.Empty;
+            }
+        }
+
         /// <summary>
         /// 从已嗅探地址里找和视频轨同组的 DASH 音频轨。
         /// 有 videoId 时优先选 URL 里包含该 ID 的音频轨，否则取最后一条 media-audio。
@@ -676,8 +1094,9 @@ namespace WinFormsApp3
 
         /// <summary>
         /// 执行一次下载。返回 null 表示成功或用户主动取消，否则返回错误信息给上层提示。
+        /// 批量下载时 promptOpenFolder 传 false，避免每条都弹“打开文件夹”。
         /// </summary>
-        private async Task<string?> TryDownloadAsync(VideoCandidate candidate, string filePath)
+        private async Task<string?> TryDownloadAsync(VideoCandidate candidate, string filePath, bool promptOpenFolder = true)
         {
             VideoDownloader downloader = await CreateDownloaderAsync(candidate);
 
@@ -706,7 +1125,7 @@ namespace WinFormsApp3
 
                 SetStatus($"已下载 {Path.GetFileName(result.FilePath)}（{VideoDownloader.FormatSize(result.Bytes)}）");
 
-                if (MessageBox.Show(this, $"视频已保存到：\n{result.FilePath}\n\n要打开所在文件夹吗？",
+                if (promptOpenFolder && MessageBox.Show(this, $"视频已保存到：\n{result.FilePath}\n\n要打开所在文件夹吗？",
                         "下载完成", MessageBoxButtons.YesNo, MessageBoxIcon.Information) == DialogResult.Yes)
                 {
                     OpenFolder(result.FilePath);
@@ -716,7 +1135,8 @@ namespace WinFormsApp3
             }
             catch (OperationCanceledException)
             {
-                // 用户主动取消就别再换地址重试了
+                // 用户主动取消就别再换地址重试了；批量路径靠这个标志中止剩余条目
+                downloadWasCanceled = true;
                 SetStatus("已取消下载");
                 return null;
             }
@@ -745,7 +1165,11 @@ namespace WinFormsApp3
             return new VideoDownloader(referer, cookie);
         }
 
-        private async Task<string?> GetCookieHeaderAsync(string url)
+        /// <summary>
+        /// 取 Cookie 也是 CoreWebView2 COM 调用，同样封送回 UI 线程，
+        /// 否则截图预览的后台任务会在这里永久卡死。
+        /// </summary>
+        private Task<string?> GetCookieHeaderAsync(string url) => OnUiAsync(async () =>
         {
             CoreWebView2? core = webView21.CoreWebView2;
             if (core == null || !Uri.TryCreate(url, UriKind.Absolute, out Uri? uri)) return null;
@@ -763,7 +1187,7 @@ namespace WinFormsApp3
                 // 拿不到 Cookie 就按匿名请求下载
                 return null;
             }
-        }
+        });
 
         private void ReportProgress(DownloadProgress value)
         {
@@ -801,6 +1225,23 @@ namespace WinFormsApp3
             }
         }
 
+        /// <summary>
+        /// 批量下载时同页多个候选可能推断出同名文件，重名时加序号避免互相覆盖。
+        /// </summary>
+        private static string UniqueFilePath(string folder, string fileName)
+        {
+            string path = Path.Combine(folder, fileName);
+            if (!File.Exists(path)) return path;
+
+            string name = Path.GetFileNameWithoutExtension(fileName);
+            string ext = Path.GetExtension(fileName);
+            for (int i = 2; ; i++)
+            {
+                path = Path.Combine(folder, $"{name} ({i}){ext}");
+                if (!File.Exists(path)) return path;
+            }
+        }
+
         private static void OpenFolder(string filePath)
         {
             try

uniapp/Google Chrome/PreviewLog.cs

@@ -0,0 +1,27 @@
+using System.Diagnostics;
+
+namespace WinFormsApp3
+{
+    /// <summary>
+    /// 截图预览诊断日志：exe 目录下 preview_debug.log。
+    /// 挂起类问题光看界面定位不到，必须把每一步（含线程号）落到磁盘上。
+    /// </summary>
+    public static class PreviewLog
+    {
+        private static readonly object Gate = new();
+        private static readonly string FilePath = Path.Combine(AppContext.BaseDirectory, "preview_debug.log");
+
+        public static void Write(string message)
+        {
+            string line = $"{DateTime.Now:HH:mm:ss.fff} [T{Thread.CurrentThread.ManagedThreadId:D2}] {message}";
+            try
+            {
+                lock (Gate) File.AppendAllText(FilePath, line + Environment.NewLine);
+            }
+            catch
+            {
+                // 日志写失败不影响功能
+            }
+        }
+    }
+}

uniapp/Google Chrome/VideoDownloader.cs

@@ -265,11 +265,24 @@ namespace WinFormsApp3
         }
 
         /// <summary>
-        /// 用 ffmpeg 把 DASH 视频轨和音频轨合并成 mp4（直接 copy 不重编码）。
+        /// 用 ffmpeg 把 DASH 视频轨和音频轨合并成 mp4。
+        /// 优先两条流直接 copy：不重编码、时间戳原样保留，音画对齐最准确；
+        /// 只有音频轨格式装不进 mp4 容器时才回退到 AAC 转码。
         /// </summary>
         private static async Task<bool> MuxDashAsync(string ffmpeg, string videoFile, string audioFile, string outputFile, CancellationToken ct)
         {
-            var args = $"-hide_banner -loglevel error -y -i \"{videoFile}\" -i \"{audioFile}\" -c:v copy -c:a aac -strict experimental -movflags +faststart \"{outputFile}\"";
+            // 只取视频轨的视频流 + 音频轨的音频流（没音频流也照常出片），-shortest 把两条轨截齐到同一时长
+            var copyArgs = $"-hide_banner -loglevel error -y -fflags +genpts -i \"{videoFile}\" -i \"{audioFile}\" -map 0:v:0 -map 1:a:0? -c copy -shortest -movflags +faststart \"{outputFile}\"";
+            if (await RunFfmpegAsync(ffmpeg, copyArgs, outputFile, ct)) return true;
+
+            TryDelete(outputFile);
+
+            var aacArgs = $"-hide_banner -loglevel error -y -fflags +genpts -i \"{videoFile}\" -i \"{audioFile}\" -map 0:v:0 -map 1:a:0? -c:v copy -c:a aac -strict experimental -shortest -movflags +faststart \"{outputFile}\"";
+            return await RunFfmpegAsync(ffmpeg, aacArgs, outputFile, ct);
+        }
+
+        private static async Task<bool> RunFfmpegAsync(string ffmpeg, string args, string outputFile, CancellationToken ct)
+        {
             var psi = new ProcessStartInfo
             {
                 FileName = ffmpeg,
@@ -291,6 +304,170 @@ namespace WinFormsApp3
             return proc.ExitCode == 0 && File.Exists(outputFile) && new FileInfo(outputFile).Length > 0;
         }
 
+        /// <summary>
+        /// 抽帧结果：成功时 Frames 非空；失败时 Error 给界面显示原因，不让用户干等。
+        /// </summary>
+        public record FrameExtraction(List<byte[]> Frames, string? Error);
+
+        /// <summary>
+        /// 抽取预览截图：每 intervalSeconds 秒取一张、共取 frameCount 张（默认 5 秒 3 张），
+        /// 供下载列表肉眼对比哪个是当前视频。用 ffmpeg 直接读远端地址，带 Referer/Cookie 过防盗链。
+        /// 单次尝试限 25 秒，超时不再重试第二次，避免地址失效时列表长时间卡在“生成中”。
+        /// </summary>
+        public async Task<FrameExtraction> ExtractFramesAsync(string url, CancellationToken ct, int intervalSeconds = 5, int frameCount = 3)
+        {
+            var ffmpeg = FindFfmpeg();
+            if (ffmpeg == null)
+            {
+                return new FrameExtraction(new List<byte[]>(), "未找到 ffmpeg，无法生成截图");
+            }
+            if (!Uri.TryCreate(url, UriKind.Absolute, out var uri)
+                || (uri.Scheme != Uri.UriSchemeHttp && uri.Scheme != Uri.UriSchemeHttps))
+            {
+                return new FrameExtraction(new List<byte[]>(), "该地址无法直接抽帧");
+            }
+
+            var tmpDir = Path.Combine(Path.GetTempPath(), Guid.NewGuid().ToString("N"));
+            Directory.CreateDirectory(tmpDir);
+
+            try
+            {
+                string? lastError = null;
+
+                // 先试从第 2 秒开始抽（片头常有黑帧），只有上一次正常退出且没拿到帧才退回 0 秒再试
+                foreach (var startAt in new[] { 2, 0 })
+                {
+                    ct.ThrowIfCancellationRequested();
+
+                    var args = new List<string>
+                    {
+                        "-hide_banner", "-loglevel", "error", "-nostdin", "-y",
+                        // 远端卡住时快速失败：单次 I/O 12 秒，探测上限 2MB/2秒，不靠外部杀进程兑底
+                        "-rw_timeout", "12000000",
+                        "-probesize", "2000000", "-analyzeduration", "2000000",
+                        "-reconnect", "1", "-reconnect_streamed", "1", "-reconnect_delay_max", "2"
+                    };
+                    var headers = BuildFfmpegHeaders();
+                    if (headers.Length > 0)
+                    {
+                        args.Add("-headers");
+                        args.Add(headers);
+                    }
+                    if (IsHlsUrl(url))
+                    {
+                        args.Add("-protocol_whitelist");
+                        args.Add("file,http,https,tcp,tls,crypto");
+                    }
+                    args.AddRange(new[]
+                    {
+                        "-ss", startAt.ToString(), "-i", url,
+                        "-t", (intervalSeconds * frameCount).ToString(),
+                        "-vf", $"fps=1/{intervalSeconds},scale=160:-2",
+                        "-frames:v", frameCount.ToString(), "-an",
+                        Path.Combine(tmpDir, "f_%d.jpg")
+                    });
+
+                    var run = await RunFfmpegArgsAsync(ffmpeg, args, ct);
+
+                    var files = Directory.GetFiles(tmpDir, "f_*.jpg").OrderBy(f => f, StringComparer.Ordinal).ToList();
+                    if (files.Count > 0)
+                    {
+                        return new FrameExtraction(files.Select(File.ReadAllBytes).ToList(), null);
+                    }
+
+                    lastError = run.Error ?? "没抽到帧";
+                    if (run.TimedOut)
+                    {
+                        break; // 地址多半已失效或被防盗链卡住，再试一次只会多等半分钟
+                    }
+                }
+
+                return new FrameExtraction(new List<byte[]>(), lastError ?? "没抽到帧");
+            }
+            finally
+            {
+                try { Directory.Delete(tmpDir, true); } catch { /* 临时目录删不掉不影响结果 */ }
+            }
+        }
+
+        /// <summary>
+        /// ffmpeg 走网络也要过防盗链：把下载器身上的 UA / Referer / Cookie 拼成 -headers 参数。
+        /// </summary>
+        private string BuildFfmpegHeaders()
+        {
+            var sb = new StringBuilder();
+            sb.Append($"User-Agent: {UserAgent}\r\n");
+            if (_referer != null) sb.Append($"Referer: {_referer}\r\n");
+            if (_cookie != null) sb.Append($"Cookie: {_cookie}\r\n");
+            return sb.ToString();
+        }
+
+        /// <summary>ffmpeg 单次运行结果：TimedOut 表示被外部杀掉，Error 给界面显示原因。</summary>
+        private record FfmpegRun(bool TimedOut, string? Error);
+
+        private static async Task<FfmpegRun> RunFfmpegArgsAsync(string ffmpeg, List<string> args, CancellationToken ct)
+        {
+            var psi = new ProcessStartInfo
+            {
+                FileName = ffmpeg,
+                UseShellExecute = false,
+                CreateNoWindow = true,
+                RedirectStandardError = true,
+                RedirectStandardOutput = true
+            };
+            foreach (var a in args) psi.ArgumentList.Add(a);
+
+            using var proc = Process.Start(psi);
+            if (proc == null) return new FfmpegRun(false, "ffmpeg 启动失败");
+
+            // 就算 -rw_timeout 失效（DNS 卡住、TLS 握手挂起等），25 秒也必须杀掉
+            using var timeout = CancellationTokenSource.CreateLinkedTokenSource(ct);
+            timeout.CancelAfter(TimeSpan.FromSeconds(25));
+
+            var errRead = proc.StandardError.ReadToEndAsync(); // 不读干 stderr 会把进程堵死
+            bool timedOut = false;
+            using (timeout.Token.Register(() => { try { if (!proc.HasExited) proc.Kill(true); } catch { } }))
+            {
+                try
+                {
+                    await proc.WaitForExitAsync(timeout.Token);
+                }
+                catch (OperationCanceledException) when (ct.IsCancellationRequested)
+                {
+                    throw; // 用户取消要往上抛，超时杀掉进程则返回原因
+                }
+                catch (OperationCanceledException)
+                {
+                    timedOut = true;
+                }
+            }
+
+            string stderr = string.Empty;
+            try { stderr = await errRead; } catch { /* 进程被杀时读流可能报错，不影响判断 */ }
+
+            if (timedOut)
+            {
+                return new FfmpegRun(true, "抽帧超时（25秒）：地址可能已失效或被防盗链卡住");
+            }
+            if (proc.ExitCode != 0)
+            {
+                return new FfmpegRun(false, SummarizeFfmpegError(stderr));
+            }
+            return new FfmpegRun(false, null);
+        }
+
+        /// <summary>取 ffmpeg 报错里最有信息量的一行，太长截断，直接丢给界面显示。</summary>
+        private static string SummarizeFfmpegError(string stderr)
+        {
+            var line = (stderr ?? string.Empty)
+                .Split('\n')
+                .Select(l => l.Trim('\r', ' '))
+                .FirstOrDefault(l => l.Length > 0 && !l.StartsWith("[h264", StringComparison.OrdinalIgnoreCase)
+                    && !l.StartsWith("[aac", StringComparison.OrdinalIgnoreCase));
+            if (string.IsNullOrEmpty(line)) return "ffmpeg 抽帧失败";
+            return line.Length > 90 ? line[..90] + "…" : line;
+        }
+
         private HttpClient CreateClient()
         {
             var client = new HttpClient(new HttpClientHandler { AllowAutoRedirect = false })

uniapp/Google Chrome/VideoListForm.Designer.cs

@@ -0,0 +1,101 @@
+namespace WinFormsApp3
+{
+    partial class VideoListForm
+    {
+        private System.ComponentModel.IContainer components = null;
+
+        protected override void Dispose(bool disposing)
+        {
+            if (disposing)
+            {
+                components?.Dispose();
+            }
+            base.Dispose(disposing);
+        }
+
+        private void InitializeComponent()
+        {
+            components = new System.ComponentModel.Container();
+            pnlVideos = new Panel();
+            panelBottom = new Panel();
+            lblHint = new Label();
+            flowButtons = new FlowLayoutPanel();
+            btnDownload = new Button();
+            btnCancel = new Button();
+            SuspendLayout();
+            // 
+            // pnlVideos
+            // 
+            pnlVideos.AutoScroll = true;
+            pnlVideos.Dock = DockStyle.Fill;
+            pnlVideos.Name = "pnlVideos";
+            // 
+            // panelBottom
+            // 
+            panelBottom.Controls.Add(flowButtons);
+            panelBottom.Controls.Add(lblHint);
+            panelBottom.Dock = DockStyle.Bottom;
+            panelBottom.Height = 48;
+            panelBottom.Name = "panelBottom";
+            // 
+            // lblHint
+            // 
+            lblHint.AutoSize = true;
+            lblHint.Location = new Point(12, 15);
+            lblHint.Name = "lblHint";
+            lblHint.Text = "正在生成预览截图…";
+            // 
+            // flowButtons
+            // 用从右往左的流式布局放按钮，避免 Anchor+固定坐标在初始化时被锚点公式推出窗外
+            // 
+            flowButtons.Controls.Add(btnCancel);
+            flowButtons.Controls.Add(btnDownload);
+            flowButtons.Dock = DockStyle.Right;
+            flowButtons.FlowDirection = FlowDirection.RightToLeft;
+            flowButtons.Location = new Point(600, 0);
+            flowButtons.Name = "flowButtons";
+            flowButtons.Size = new Size(300, 48);
+            flowButtons.WrapContents = false;
+            // 
+            // btnDownload
+            // 
+            btnDownload.Margin = new Padding(0, 9, 8, 9);
+            btnDownload.Name = "btnDownload";
+            btnDownload.Size = new Size(150, 30);
+            btnDownload.Text = "下载选中 (0)";
+            btnDownload.UseVisualStyleBackColor = true;
+            btnDownload.Click += btnDownload_Click;
+            // 
+            // btnCancel
+            // 
+            btnCancel.DialogResult = DialogResult.Cancel;
+            btnCancel.Margin = new Padding(0, 9, 4, 9);
+            btnCancel.Name = "btnCancel";
+            btnCancel.Size = new Size(88, 30);
+            btnCancel.Text = "取消";
+            btnCancel.UseVisualStyleBackColor = true;
+            // 
+            // VideoListForm
+            // 
+            CancelButton = btnCancel;
+            AcceptButton = btnDownload;
+            ClientSize = new Size(900, 640);
+            Controls.Add(pnlVideos);
+            Controls.Add(panelBottom);
+            MinimumSize = new Size(640, 400);
+            Name = "VideoListForm";
+            StartPosition = FormStartPosition.CenterParent;
+            Text = "本页视频列表（截图预览，勾选后批量下载）";
+            panelBottom.ResumeLayout(false);
+            panelBottom.PerformLayout();
+            ResumeLayout(false);
+        }
+
+        private Panel pnlVideos;
+        private Panel panelBottom;
+        private Label lblHint;
+        private FlowLayoutPanel flowButtons;
+        private Button btnDownload;
+        private Button btnCancel;
+    }
+}

uniapp/Google Chrome/VideoListForm.cs

@@ -0,0 +1,341 @@
+using System.Drawing.Drawing2D;
+
+namespace WinFormsApp3
+{
+    /// <summary>
+    /// 本页视频下载列表：每个候选视频用 ffmpeg 抽 3 张间隔 5 秒的截图拼成预览条，
+    /// 肉眼对比哪个是当前视频后勾选，选文件夹批量下载。
+    /// 当前正在播放的那条默认勾上。
+    /// </summary>
+    public partial class VideoListForm : Form
+    {
+        private const int RowHeight = 124;
+        private const int PreviewWidth = 496;
+        private const int PreviewHeight = 100;
+
+        private readonly Func<VideoCandidate, CancellationToken, Task<(Image? Image, string? Error)>> _previewFactory;
+        private readonly List<VideoRow> _rows = new();
+        private readonly CancellationTokenSource _loadCts = new();
+        private int _generatedCount;
+        private int _failedCount;
+
+        /// <summary>点“下载选中”后带回的勾选候选（按列表顺序）。</summary>
+        public List<VideoCandidate> SelectedCandidates { get; } = new();
+
+        public VideoListForm(IReadOnlyList<VideoCandidate> candidates, IReadOnlyCollection<string> currentUrls,
+            Func<VideoCandidate, CancellationToken, Task<(Image? Image, string? Error)>> previewFactory)
+        {
+            InitializeComponent();
+
+            _previewFactory = previewFactory;
+            BuildRows(candidates, currentUrls);
+        }
+
+        private void BuildRows(IReadOnlyList<VideoCandidate> candidates, IReadOnlyCollection<string> currentUrls)
+        {
+            int y = 8;
+            foreach (VideoCandidate candidate in candidates)
+            {
+                bool isCurrent = currentUrls.Contains(candidate.Url);
+                VideoRow row = new VideoRow(candidate, Describe(candidate, isCurrent), isCurrent)
+                {
+                    Location = new Point(8, y),
+                    Width = Math.Max(620, pnlVideos.ClientSize.Width - 24),
+                };
+                row.CheckChanged += (_, _) => UpdateSelectionCount();
+                _rows.Add(row);
+                pnlVideos.Controls.Add(row);
+                y += RowHeight + 6;
+            }
+
+            pnlVideos.Resize += (_, _) =>
+            {
+                foreach (VideoRow row in _rows)
+                {
+                    row.Width = Math.Max(620, pnlVideos.ClientSize.Width - 24);
+                }
+            };
+
+            UpdateSelectionCount();
+        }
+
+        /// <summary>
+        /// 截图预览在后台生成（三条并发），生成一条刷新一条；
+        /// 失败时把原因直接写在预览条上，不让界面一直停在“生成中…”。
+        /// </summary>
+        protected override async void OnShown(EventArgs e)
+        {
+            base.OnShown(e);
+
+            if (_rows.Count == 0)
+            {
+                lblHint.Text = "本页没有可下载的视频";
+                return;
+            }
+
+            SemaphoreSlim semaphore = new SemaphoreSlim(3);
+            Task[] tasks = _rows.Select(async row =>
+            {
+                await semaphore.WaitAsync(_loadCts.Token);
+                try
+                {
+                    Image? preview = null;
+                    string? error = null;
+                    try
+                    {
+                        (preview, error) = await _previewFactory(row.Candidate, _loadCts.Token);
+                    }
+                    catch (OperationCanceledException)
+                    {
+                        PreviewLog.Write("预览任务被取消（列表已关闭）");
+                        return;
+                    }
+                    catch (Exception ex)
+                    {
+                        // 抽帧失败按“无预览”处理，勾选与下载不受影响
+                        error = ex.Message;
+                    }
+
+                    PreviewLog.Write($"预览回传 UI img={(preview != null ? "ok" : "null")} error={(error ?? "-")}");
+
+                    if (_loadCts.IsCancellationRequested || !IsHandleCreated || IsDisposed)
+                    {
+                        preview?.Dispose();
+                        return;
+                    }
+
+                    BeginInvoke(() =>
+                    {
+                        row.SetResult(preview, error);
+                        if (preview == null) _failedCount++;
+                        _generatedCount++;
+                        // 最后一行刷新时直接切到完成文案，不依赖 WhenAll 后续代码的时序
+                        lblHint.Text = _generatedCount < _rows.Count
+                            ? $"截图生成中… {_generatedCount}/{_rows.Count}" +
+                              (_failedCount > 0 ? $"（{_failedCount} 条失败，原因见预览条）" : string.Empty)
+                            : (_failedCount == 0
+                                ? "截图已生成，对比后勾选要下载的视频"
+                                : $"截图生成完毕（{_failedCount} 条失败，原因见预览条；不影响勾选下载）");
+                    });
+                }
+                finally
+                {
+                    semaphore.Release();
+                }
+            }).ToArray();
+
+            await Task.WhenAll(tasks);
+
+            if (!IsDisposed && !_loadCts.IsCancellationRequested)
+            {
+                lblHint.Text = _failedCount == 0
+                    ? "截图已生成，对比后勾选要下载的视频"
+                    : $"截图生成完毕（{_failedCount} 条失败，原因见预览条；不影响勾选下载）";
+            }
+        }
+
+        protected override void OnFormClosed(FormClosedEventArgs e)
+        {
+            _loadCts.Cancel();
+            _loadCts.Dispose();
+            base.OnFormClosed(e);
+        }
+
+        private void UpdateSelectionCount()
+        {
+            btnDownload.Text = $"下载选中 ({_rows.Count(r => r.IsChecked)})";
+        }
+
+        private void btnDownload_Click(object sender, EventArgs e)
+        {
+            SelectedCandidates.Clear();
+            SelectedCandidates.AddRange(_rows.Where(r => r.IsChecked).Select(r => r.Candidate));
+
+            if (SelectedCandidates.Count == 0)
+            {
+                MessageBox.Show(this, "先勾选要下载的视频（看截图对比哪个是当前视频）。",
+                    "下载列表", MessageBoxButtons.OK, MessageBoxIcon.Information);
+                return;
+            }
+
+            DialogResult = DialogResult.OK;
+        }
+
+        private static string Describe(VideoCandidate candidate, bool isCurrent)
+        {
+            List<string> tags = new List<string>();
+            if (isCurrent) tags.Add("当前播放");
+            if (candidate.PlaylistText != null) tags.Add("内存播放列表");
+            else if (VideoDownloader.IsHlsUrl(candidate.Url)) tags.Add("m3u8");
+            if (!string.IsNullOrEmpty(candidate.AudioUrl)) tags.Add("音频轨已配对·自动合并");
+            if (tags.Count == 0) tags.Add("直链");
+
+            string hostLine;
+            try
+            {
+                Uri u = new Uri(candidate.Url);
+                string last = Path.GetFileName(u.AbsolutePath);
+                hostLine = last.Length > 0 ? $"{u.Host} … {last}" : u.Host;
+            }
+            catch
+            {
+                hostLine = candidate.Url.Length > 90 ? candidate.Url[..90] + "…" : candidate.Url;
+            }
+
+            return $"【{string.Join("】【", tags)}】\n{hostLine}";
+        }
+
+        /// <summary>
+        /// 把抽到的 JPEG 帧横向拼成一条预览图（约 3×160 宽），供列表行显示。
+        /// </summary>
+        public static Image? ComposeFrames(List<byte[]> frames)
+        {
+            if (frames == null || frames.Count == 0) return null;
+
+            List<Image> source = new List<Image>();
+            foreach (byte[] frame in frames)
+            {
+                try
+                {
+                    Image img = Image.FromStream(new MemoryStream(frame));
+                    source.Add(img);
+                }
+                catch
+                {
+                    // 坏帧直接跳过
+                }
+            }
+            if (source.Count == 0) return null;
+
+            const int cellW = 160;
+            const int gap = 8;
+            int cellH = PreviewHeight - 4;
+
+            var sizes = source.Select(img =>
+            {
+                int w = cellW;
+                int h = Math.Max(1, (int)Math.Round((double)cellW * img.Height / img.Width));
+                if (h > cellH)
+                {
+                    h = cellH;
+                    w = Math.Max(1, (int)Math.Round((double)cellH * img.Width / img.Height));
+                }
+                return (w, h);
+            }).ToList();
+
+            int canvasW = source.Count * cellW + (source.Count - 1) * gap;
+            int canvasH = sizes.Max(s => s.h);
+            Bitmap strip = new Bitmap(canvasW, canvasH);
+
+            using (Graphics g = Graphics.FromImage(strip))
+            {
+                g.Clear(Color.Black);
+                g.InterpolationMode = InterpolationMode.HighQualityBicubic;
+                for (int i = 0; i < source.Count; i++)
+                {
+                    int x = i * (cellW + gap) + (cellW - sizes[i].w) / 2;
+                    int y = (canvasH - sizes[i].h) / 2;
+                    g.DrawImage(source[i], new Rectangle(x, y, sizes[i].w, sizes[i].h));
+                }
+            }
+
+            foreach (Image img in source) img.Dispose();
+            return strip;
+        }
+
+        /// <summary>
+        /// 一行候选：勾选框 + 截图预览条 + 说明文字。
+        /// </summary>
+        private sealed class VideoRow : UserControl
+        {
+            private readonly CheckBox _check = new();
+            private readonly PictureBox _preview = new();
+            private readonly ToolTip _tip = new();
+
+            public VideoCandidate Candidate { get; }
+            public bool IsChecked => _check.Checked;
+            public event EventHandler? CheckChanged;
+
+            public VideoRow(VideoCandidate candidate, string description, bool isChecked)
+            {
+                Candidate = candidate;
+                Height = RowHeight;
+                Margin = new Padding(0);
+
+                TableLayoutPanel layout = new TableLayoutPanel
+                {
+                    Dock = DockStyle.Fill,
+                    ColumnCount = 3,
+                    RowCount = 1,
+                };
+                layout.ColumnStyles.Add(new ColumnStyle(SizeType.Absolute, 30F));
+                layout.ColumnStyles.Add(new ColumnStyle(SizeType.Absolute, PreviewWidth + 8F));
+                layout.ColumnStyles.Add(new ColumnStyle(SizeType.Percent, 100F));
+
+                _check.Dock = DockStyle.None;
+                _check.Anchor = AnchorStyles.Top;
+                _check.Location = new Point(4, 6);
+                _check.Checked = isChecked;
+                _check.CheckedChanged += (_, _) => CheckChanged?.Invoke(this, EventArgs.Empty);
+
+                _preview.Size = new Size(PreviewWidth, PreviewHeight);
+                _preview.SizeMode = PictureBoxSizeMode.Zoom;
+                _preview.BackColor = Color.FromArgb(28, 28, 28);
+                _preview.Image = Placeholder();
+
+                Label text = new Label
+                {
+                    Dock = DockStyle.Fill,
+                    Padding = new Padding(8, 4, 4, 2),
+                    Text = description,
+                    TextAlign = ContentAlignment.TopLeft,
+                };
+
+                layout.Controls.Add(_check, 0, 0);
+                layout.Controls.Add(_preview, 1, 0);
+                layout.Controls.Add(text, 2, 0);
+                Controls.Add(layout);
+            }
+
+            public void SetResult(Image? image, string? error)
+            {
+                _preview.Image?.Dispose();
+                if (image != null)
+                {
+                    _preview.Image = image;
+                    _tip.SetToolTip(_preview, string.Empty);
+                }
+                else
+                {
+                    // 把失败原因直接画在预览条上，一眼能看出是超时还是防盗链
+                    string reason = string.IsNullOrWhiteSpace(error) ? "截图不可用" : error!;
+                    _preview.Image = Placeholder(reason);
+                    _tip.SetToolTip(_preview, reason);
+                }
+            }
+
+            /// <summary>截图还没生成好（或生成失败）时行内显示的占位条。</summary>
+            private static Image Placeholder(string? message = null)
+            {
+                Bitmap bmp = new Bitmap(PreviewWidth, PreviewHeight);
+                using Graphics g = Graphics.FromImage(bmp);
+                g.Clear(Color.FromArgb(28, 28, 28));
+                using (var cellBrush = new SolidBrush(Color.FromArgb(56, 56, 56)))
+                {
+                    for (int i = 0; i < 3; i++)
+                    {
+                        g.FillRectangle(cellBrush, i * 168, 0, 160, PreviewHeight);
+                    }
+                }
+                using Font font = new Font("Microsoft YaHei UI", 8F);
+                string text = message ?? "截图生成中…";
+                Color color = message == null ? Color.Gray : Color.FromArgb(230, 140, 90);
+                // 失败原因可能较长，在预览条区域内自动换行
+                var rect = new RectangleF(4, 4, PreviewWidth - 8, PreviewHeight - 8);
+                using var format = new StringFormat { Trimming = StringTrimming.EllipsisCharacter, FormatFlags = StringFormatFlags.LineLimit };
+                g.DrawString(text, font, new SolidBrush(color), rect, format);
+                return bmp;
+            }
+        }
+    }
+}

uniapp/Google Chrome/currentLink.txt

@@ -0,0 +1 @@
+https://www.douyin.com/jingxuan?modal_id=7704345703665422713