Delphi 的 Dll 函数的 调用

一、Dll建立
（一）DLL项目的建立
library mydll;
 
uses
base in 'base.pas';
 
exports
Triple name 'Tr';
 
{$R *.res}
 
begin
end.
 
（二）函数单元
unit base;
 
interface
 
uses windows;
 
function Triple(N:integer):integer;stdcall;
 
implementation
 
function Triple(N:integer):integer;stdcall;
begin
result:=n*3;
end;
 
end.
 
 
二、静态调用
 
unit Unit1;
 
interface
 
uses
Windows, SysUtils, Controls, Forms,
StdCtrls, Classes;
 
type
TForm1 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    procedure Button1Click(Sender: TObject);
private
    { Private declarations }
public
    { Public declarations }
end;
 
var
Form1: TForm1;
 
implementation
 
const
gdi32='mydll';
function triple(n:integer):integer;stdcall;external gdi32 name 'Tr';
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
begin
edit1.Text:=inttostr(triple(10));
end;
 
end.
 
三、动态调用
unit Unit2;
 
interface
 
uses
Windows, SysUtils, Controls, Forms,
StdCtrls, Classes;
 
type
TForm1 = class(TForm)
    Button1: TButton;
    Edit1: TEdit;
    procedure Button1Click(Sender: TObject);
private
    { Private declarations }
public
    { Public declarations }
end;
 
var
Form1: TForm1;
 
implementation
 
{$R *.dfm}
 
procedure TForm1.Button1Click(Sender: TObject);
type
   Taddc=function(n:integer):integer;stdcall;//定义函数指针
var
Handle:Thandle;
addc:Taddc;
begin
Handle:=LoadLibrary('mydll.dll');//加载mydll
if Handle>32 then
begin
   @addc:=GetProcAddress(Handle,'Tr'); //取Tr函数入口地址，大小写敏感。Tr为mydll中的Triple的exports 的name命名
   if @a