我的EXE是DELPHI做的,目的是接收SQL触发器传来的字符串,然后通后消息把字符串传给另一个正在运行的程序,
能找到另一个程序的PID(进程ID),但无法找到另一个在运行程序的窗口句柄.因此就无法接收到消息,

后来想到一个办法,把另一个运行的程序运行时窗体的句柄放在一个INI文件中,这样就不用找这个窗口的句柄了,直接读INI就可得到,但调用SendMessage(winhand, WM_COPYDATA, 1, Integer(@Data));仍不能正常传递消息.

发送消息程序
program send;

{$APPTYPE CONSOLE}

uses
  Forms,
  windows,
  sysutils,
  Messages,
  WinProcs,
  inifiles,
  all in 'all.pas';

var
  Data: tagCOPYDATASTRUCT;
  pBuf: PAnsiChar;
  MYHWND: THandle;
  inifile: TIniFile;
  winhand:integer;
{$R *.res}

begin
  Application.Initialize;
  Application.MainFormOnTaskbar := True;
    Application.Run;

begin
   if FileExists(Trim(ExtractFilePath(Application.ExeName)+'com.ini')) = True then
    begin
    Try
      inifile := TIniFile.Create(Trim(ExtractFilePath(Application.ExeName))+'com.ini');
      winhand:= strtoint(inifile.ReadString('配置信息','窗口句柄','1'));
    Finally
      inifile.Free;
    end;
   end;
  GetMem(pBuf, Length(ParamStr(1)) + 1);
try

    ZeroMemory(pBuf, Length(ParamStr(1)) + 1);
    StrPCopy(pBuf,ParamStr(1));
    Data.cbData:= Length(ParamStr(1));
    Data.dwData:= Length(ParamStr(1));
    Data.lpData:= pBuf;
    writeln(ParamStr(1));
    SendMessage(winhand, WM_COPYDATA, 1, Integer(@Data));
    writeln(winhand);
  finally
    FreeMem(pBuf);
end;
end;

  sleep(3000);
end.

接收消息程序
unit Unit2;

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls,inifiles;
const
 My_MousL=WM_USER+100;
type
  TForm2 = class(TForm)
    Label1: TLabel;
    procedure FormShow(Sender: TObject);
  private
  j:integer;
    { Private declarations }
  public
 procedure Mymessage(var t:TMessage);message WM_COPYDATA;

    { Public declarations }
  end;

var
  Form2: TForm2;

implementation

{$R *.dfm}

procedure TForm2.FormShow(Sender: TObject);
var inifile:tinifile;
begin
 if FileExists(Trim(ExtractFilePath(Application.ExeName)+'com.ini')) = True then
  begin
    Try
      inifile := TIniFile.Create(Trim(ExtractFilePath(Application.ExeName))+'com.ini');
       inifile.WriteString('配置信息','窗口句柄',inttostr(findwindow(nil,'form2')));
    Finally
      inifile.Free;
    end;
  end
end;

procedure Tform2.Mymessage(var t: TMessage);
var
  Data  : ^tagCOPYDATASTRUCT;
  strMSG: string;
  mylen:integer;
begin
  Data:= Pointer(t.LParam);
   mylen:=integer(data.cbData);
  strMSG:= copy(PAnsichar(Data.lpData),1,mylen);

 label1.Caption:=strMsg;

end;


end.