1 delphi编写DLL  2 下面在delphi中编写一个简单的dll，在该dll中只有一个max函数，返回2个数中的大数(Delphi 5.0)  3 1、New->DLL;取名为DLL_0001,编写代码:  4 library dll_0001;  5 uses  6    SysUtils,  7    Classes;  8 {$R *.RES}  9 function max(x,y:integer):integer;stdcall; 10 begin 11      if(x>y) then 12       max :=x 13       else 14       max :=y; 15 end; 16 exports max; 17 begin 18 end. 19 红色部分为自己编写,这里和普通的delphi函数是一样的，只是在返回值中带个stdcall参数，然后用exports把函数导出 20 ================================================================================ 21 Delphl调用dll 22 调用dll分动态调用和静态调用2中，动态调用写起来简单，安全点，动态调用复杂很多，但很灵活; 23 现在编写一个程序，来调用上面写的dll_0001.dll文件中的max函数 24 一、new一个Application，在Form中放入2个TEdit、1个TLabek； 25 二、 26 1、静态调用 27 unit Unit1; 28 interface 29 uses 30    Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 31    StdCtrls; 32 type 33    TForm1 = class(TForm) 34      Edit1: TEdit; 35      Edit2: TEdit; 36      Label1: TLabel; 37      procedure Edit2KeyDown(Sender: TObject; var Key: Word; 38        Shift: TShiftState); 39    private 40      { Private declarations } 41    public 42      { Public declarations } 43    end; 44 var 45    Form1: TForm1; 46 implementation 47 {$R *.DFM} 48 function max(x,y:integer):integer;stdcall; 49 external ‘dll_0001.dll‘; 50 procedure TForm1.Edit2KeyDown(Sender: TObject; var Key: Word; 51    Shift: TShiftState); 52 begin 53 if key =vk_return then 54 label1.Caption :=IntToStr(max(StrToInt(Edit1.text),StrToInt(edit2.text))); 55 end; 56 end. 57 红色代码自己添加，其中external "dll_name"中的dll_name可以是dll的绝对路径，要是该dll文件在你的搜索路径中，可以直接写文件名，但是.dll不能少写 58 2、动态调用,代码如下; 59 unit Unit1; 60 interface 61 uses 62    Windows, Messages, SysUtils, Classes, Graphics, Controls, Forms, Dialogs, 63    StdCtrls; 64 type 65    TForm1 = class(TForm) 66      Edit1: TEdit; 67      Edit2: TEdit; 68      Label1: TLabel; 69      procedure Edit2KeyDown(Sender: TObject; var Key: Word; 70        Shift: TShiftState); 71    private 72      { Private declarations } 73    public 74      { Public declarations } 75    end; 76 var 77    Form1: TForm1; 78 implementation 79 {$R *.DFM} 80 procedure TForm1.Edit2KeyDown(Sender: TObject; var Key: Word; 81    Shift: TShiftState); 82 type 83 TFunc =function(x,y:integer):integer;stdcall; 84 var 85 Th:Thandle; 86 Tf:TFunc; 87 Tp:TFarProc; 88 begin 89 if key =vk_return then 90 begin 91 Th :=LoadLibrary(‘dll_0001.dll‘);    {load dll} 92 if(Th   >0) then 93 try 94 Tp :=GetProcAddress(Th,PChar(‘max‘)); 95 if(Tp <>nil) then 96 begin         { begin 1} 97 Tf :=TFunc(Tp); 98 Label1.Caption :=IntToStr( 99 Tf(StrToInt(Edit1.text),StrToInt(Edit2.text)));100 end   { end 1}101 else102    ShowMessage(‘function max not found.‘);103 finally104 FreeLibrary(Th);105 end106 else107 ShowMessage(‘dll_0001.dll not exsit.‘);108 109 end;110 end;111 end.