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Delphi的TDictionary,my Value对象作为null插入

tdictionary tlist delphi

Ryan · 技术社区 · 15 年前

g_FileHandlers : TDictionary<String, TList<String>>;

所以我初始化TDictionary如下:

g_FileHandlers := TDictionary<String, TList<String>>.Create;

我有一个TList,我也在初始化它,这样我就可以用它来填充TDictionary。我循环使用一些用于填充TList/TDictionary的文件数据,并尝试重新使用相同的TList作为值插入TDictionary。在第一次插入到TDictionary时,该项的TList值存在并包含数据。在第二次迭代和随后的迭代中,尽管TList值都是nil。

g_FilePaths := TList<String>.Create;

在我看来,这一切都是通过参考来实现的。如何通过值而不是引用将TList添加到我的TDictionary?

  // Create our dictionary of files and handlers
  for i := 0 to g_FileList.Count - 1 do
  begin
    g_HandlerName := AnsiMidStr(g_FileList[i], 2, Length(g_FileList[i]));
    g_HandlerName := AnsiMidStr(g_HandlerName, 1, Pos('"', g_HandlerName) - 1);

    if i = 0 then
      g_PreviousHandlerName := g_HandlerName;

    if AnsiCompareText(g_HandlerName, g_PreviousHandlerName) = 0 then
    begin
      g_FilePath := AnsiMidStr(g_FileList[i], Length(g_HandlerName) + 5, Length(g_FileList[i]));
      g_FilePath := AnsiMidStr(g_FilePath, 1, Length(g_FilePath) - 1);
      g_FilePaths.Add(g_FilePath);
    end
    else
    begin
      g_FileHandlers.Add(g_PreviousHandlerName, g_FilePaths);

      g_FilePaths.Clear;
      g_FilePath := AnsiMidStr(g_FileList[i], Length(g_HandlerName) + 5, Length(g_FileList[i]));
      g_FilePath := AnsiMidStr(g_FilePath, 1, Length(g_FilePath) - 1);
      g_FilePaths.Add(g_FilePath);
    end;

    if AnsiCompareText(g_HandlerName, g_PreviousHandlerName) <> 0 then
      g_PreviousHandlerName := g_HandlerName;

    if i = g_FileList.Count - 1 then
      g_FileHandlers.Add(g_HandlerName, g_FilePaths);
  end;
  g_FilePaths.Free;