SendInput 显示乱序发送的数据

Question

我正在通过向备忘录发送字符串来试验 SendInput。我将 SendInput 命令与对 Memo.Lines.Add('....') 的调用混合使用。令我惊讶的是，所有 Memo.Lines.Add 命令都在任何 SendInput 例程之前执行。为什么？如何让备忘录以正确的顺序显示信息？

我的代码如下所示：

procedure TForm1.Button1Click(Sender: TObject);
const
  AStr = '123 !@# 890 *() abc ABC';
var
  i: integer;
  KeyInputs: array of TInput;

  procedure KeybdInput(VKey: Byte; Flags: DWORD);
  begin
    SetLength(KeyInputs, Length(KeyInputs)+1);
    KeyInputs[high(KeyInputs)].Itype := INPUT_KEYBOARD;
    with  KeyInputs[high(KeyInputs)].ki do
    begin
      wVk := VKey;
      wScan := MapVirtualKey(wVk, 0);
      dwFlags := Flags;
    end;
  end;

begin
  Memo1.SetFocus;
  Memo1.Lines.Add('AStr := ' + AStr);

  Memo1.Lines.Add('');
  Memo1.Lines.Add('Use:   KeybdInput(ord(AStr[i]),0)');
  SetLength(KeyInputs,0);
  for i := 1 to Length(AStr) do KeybdInput(ord(AStr[i]),0);
  SendInput(Length(KeyInputs), KeyInputs[0], SizeOf(KeyInputs[0]));

  Memo1.Lines.Add('');
  Memo1.Lines.Add('Use:   KeybdInput(vkKeyScan(AStr[i]),0)');
  SetLength(KeyInputs,0);
  for i := 1 to Length(AStr) do KeybdInput(vkKeyScan(AStr[i]),0);
  SendInput(Length(KeyInputs), KeyInputs[0], SizeOf(KeyInputs[0]));
end;

我希望结果是这样的：

但实际上是这样的：

Answer 1

您使用 SendInput 发送的键盘输入通过 Windows 消息系统并最终进入您的应用程序消息队列。在您退出 Button1Click().

之前，消息队列未被处理

When something gets added to a queue, it takes time for it to come out the front of the queue

要按您期望的顺序查看事件，您需要在每个 SendInput() 之后插入对 Application.Processmessages() 的调用。尽管通常不建议调用 Application.ProcessMessages()：

The Dark Side of Application.ProcessMessages in Delphi Applications

SendInput 显示乱序发送的数据

SendInput showing data sent out of sequence

delphi

memo

sendinput