delphi - 控制台应用程序中的 TIdTCPServer.OnExecute

Question

我需要编写一个 Delphi 2009 应用程序，它从套接字读取数据。为此，我需要为 TIdTCPServer.OnExecute 事件编写一个事件处理程序。

我发现了很多在 GUI 应用程序中实现此功能的示例，但我需要在控制台应用程序(没有任何窗口)中执行此操作。

我应该如何修改下面的代码以添加一个事件处理程序(将其附加到 TCPServer)，该事件处理程序将收到的每条消息打印到调试输出中？

unit ReceivingThreadUnit;

interface

uses
  Classes,
  IdTCPServer,
  IdSocketHandle,

  SysUtils,
  Windows;

type
  ReceivingThread = class(TThread)
    private
      TCPServer: TIdTCPServer;
    public
      procedure Run();

  end;

implementation

procedure ReceivingThread.Run();
var
  Bindings: TIdSocketHandles;
begin
  TCPServer := TIdTCPServer.Create(nil);

  //setup and start TCPServer
  Bindings := TIdSocketHandles.Create(TCPServer);
  try
    with Bindings.Add do
    begin
      IP := '127.0.0.1';
      Port := 9998;
    end;
    try
      TCPServer.Bindings:=Bindings;
      // Here I want to attach TCPServer to an OnExecute event handler
      TCPServer.Active:=True;
    except on E:Exception do
      OutputDebugString(PChar(E.ToString));
    end;
  finally
    Bindings.Free;
    TCPServer.Free;
  end;
  TCPServer.Active := true;
end;

end.

Answer 1

正如 David 所说(但没有完全展示)，您需要在线程类中声明一个方法，然后将其分配给 OnExecute 事件。

顺便说一句，您不应该手动创建 TIdSocketHandles 集合。改为在现有 TIdTCPServer.Bindings 集合上调用 Add()。

试试这个:

unit ReceivingThreadUnit;

interface

uses
  Classes,
  IdTCPServer,
  IdSocketHandle,
  IdContext,

  SysUtils,
  Windows;

type
  ReceivingThread = class(TThread)
  private
    TCPServer: TIdTCPServer;
    procedure ExecuteHandler(AContext: TIdContext);
  public
    procedure Run;
  end;

implementation

procedure ReceivingThread.ExecuteHandler(AContext: TIdContext);
begin
  //...
end;

procedure ReceivingThread.Run;
begin
  //setup and start TCPServer
  TCPServer := TIdTCPServer.Create(nil);
  try
    with TCPServer.Bindings.Add do
    begin
      IP := '127.0.0.1';
      Port := 9998;
    end;
    TCPServer.OnExecute := ExecuteHandler;
    try
      TCPServer.Active := True;
    except
      on E: Exception do
        OutputDebugString(PChar(E.ToString));
    end;
    while not Terminated do
      Sleep(1000);
    TCPServer.Active := False;
  finally
    TCPServer.Free;
  end;
end;

end.

话虽如此，您的接收线程实际上非常多余，因为 TIdTCPServer 已经是多线程的，因此您也可以完全消除线程类:

program MyApp;

{$APPTYPE CONSOLE}

{$R *.res}

uses
  Classes,
  IdTCPServer,
  IdSocketHandle,
  IdContext,

  SysUtils,
  Windows;

type
  TCPServerEvents = class
  public
    class procedure ExecuteHandler(AContext: TIdContext);
  end;

class procedure TCPServerEvents.ExecuteHandler(AContext: TIdContext);
begin
  //...
end;

var
  TCPServer: TIdTCPServer;
begin
  //setup and start TCPServer
  TCPServer := TIdTCPServer.Create(nil);
  try
    with TCPServer.Bindings.Add do
    begin
      IP := '127.0.0.1';
      Port := 9998;
    end;

    TCPServer.OnExecute := TCPServerEvents.ExecuteHandler;

    try
      TCPServer.Active := True;
    except
      on E: Exception do
        OutputDebugString(PChar(E.ToString));
    end;

    while (not stop condition) do
      Sleep(1000);

    TCPServer.Active := False;
  finally
    TCPServer.Free;
  end;
end.