在delphi中，DLL加载时做初始化的Demo

library DLLEntry;//dll源码  
  
uses  
  SysUtils,  
  Classes,  
  Dialogs,  
  Windows;  
  
{$R *.res}  
  
procedure DLLEntryPoint(dwReason : DWord);  
begin  
  case dwReason of  
    DLL_PROCESS_ATTACH : showMessage('映射到进程地址空间');  
    DLL_PROCESS_DETACH : showMessage('从进程的地址空间分离出来');  
    DLL_THREAD_ATTACH :  showMessage('创建了一个新线程');  
    DLL_THREAD_DETACH : showMessage('一个线程正在退出');  
  end;  
end;  
  
begin  
  {首先，把一个过程的指针赋给DLLProc变量}  
  DLLProc := @DLLEntryPoint;  
  {调用这个过程}  
  DLLEntryPoint(DLL_PROCESS_ATTACH);  
end.  
[delphi] view plaincopy
unit mainfrm;//exe源码  
  
interface  
  
uses  
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,  
  Dialogs, StdCtrls, Buttons;  
  
type  
  //定义一个测试线程  
  TTestThread = class(TThread)  
    procedure Execute; override;  
  end;  
  TMainForm = class(TForm)  
    btnLoadLib: TBitBtn;  
    btnFreeLib: TBitBtn;  
    BtnCreateThread: TBitBtn;  
    BtnFreeThread: TBitBtn;  
    lblCount: TLabel;  
    procedure btnLoadLibClick(Sender: TObject);  
    procedure btnFreeLibClick(Sender: TObject);  
    procedure BtnCreateThreadClick(Sender: TObject);  
    procedure BtnFreeThreadClick(Sender: TObject);  
    procedure FormCreate(Sender: TObject);  
  private  
    LibHandle: THandle;  
    TestThread: TTestThread;  
    Counter: integer;  
    GoThread: Boolean;  
    { Private declarations }  
  public  
    { Public declarations }  
  end;  
  
var  
  MainForm: TMainForm;  
  
implementation  
  
{$R *.dfm}  
  
//线程执行过程  
procedure TTestThread.Execute;  
begin  
  while MainForm.GoThread do  
  begin  
    MainForm.lblCount.Caption := IntTostr(MainForm.Counter);  
    Inc(MainForm.Counter);  
  end;  
end;  
  
procedure TMainForm.FormCreate(Sender: TObject);  
begin  
  LibHandle := 0;  
  TestThread := nil;  
end;  
  
  
//这个过程用于调入动态链接库DLLEntry.dll  
procedure TMainForm.btnLoadLibClick(Sender: TObject);  
begin  
  if LibHandle = 0 then  
  begin  
    LibHandle := LoadLibrary('DLLEntry.dll');  
    if LibHandle = 0 then  
      raise Exception.Create('Unable to Load DLL');  
  end  
  else  
    MessageDlg('Library already Loaded', mtWarning, [mbok], 0);  
end;  
  
//这个过程用于释放链接库  
procedure TMainForm.btnFreeLibClick(Sender: TObject);  
begin  
  if not (LibHandle = 0) then  
  begin  
    FreeLibrary(LibHandle);  
    LibHandle := 0;  
  end;  
end;  
  
//创建一个线程  
procedure TMainForm.BtnCreateThreadClick(Sender: TObject);  
begin  
  if TestThread = nil then  
  begin  
    GoThread := True;  
    TestThread := TTestThread.Create(false);  
  end;  
end;  
  
//释放一个线程  
procedure TMainForm.BtnFreeThreadClick(Sender: TObject);  
begin  
  if not (TestThread = nil) then  
  begin  
    GoThread := False;  
    TestThread.Free;  
    TestThread := nil;  
    Counter := 0;  
  end;  
end;  
end.