delphi - 如何使用 TIdHTTP 停止(取消)下载

Question

我正在线程中使用 TIdHTTP.Get 过程来下载文件。我的问题是如何停止(取消)文件的下载？

Answer 1

我会尝试通过使用 Abort 抛出静默异常来取消它TIdHTTP.OnWork中的方法事件。此事件会在读/写操作时触发，因此在下载过程中也会触发。

type
  TDownloadThread = class(TThread)
  private
    FIdHTTP: TIdHTTP;
    FCancel: boolean;
    procedure OnWorkHandler(ASender: TObject; AWorkMode: TWorkMode; 
      AWorkCount: Integer);
  public
    constructor Create(CreateSuspended: Boolean);
    property Cancel: boolean read FCancel write FCancel;
  end;

constructor TDownloadThread.Create(CreateSuspended: Boolean);
begin
  inherited Create(CreateSuspended);
  FIdHTTP := TIdHTTP.Create(nil);
  FIdHTTP.OnWork := OnWorkHandler;
end;

procedure TDownloadThread.OnWorkHandler(ASender: TObject; AWorkMode: TWorkMode;
  AWorkCount: Integer);
begin
  if FCancel then
  begin
    FCancel := False;
    Abort;
  end;
end;

或者正如这里提到的，要直接断开连接，您可以使用 Disconnect同一事件中的方法。

procedure TDownloadThread.OnWorkHandler(ASender: TObject; AWorkMode: TWorkMode;
  AWorkCount: Integer);
begin
  if FCancel then
  begin
    FCancel := False;
    FIdHTTP.Disconnect;
  end;
end;