问题来源: http://www.cnblogs.com/del/archive/2008/12/20/985931.html#1408308
本例效果图:
Dll 文件:
本例效果图:
Dll 文件:
library Lib; uses SysUtils, Classes; {$R *.res} procedure Test(p: PChar); const Title = 'Title '; var str: string; begin str := p; StrCopy(p, Title); StrCat(p, PChar(str)); end; exports Test; begin end.调用的代码文件:
unit Unit1; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs, StdCtrls; type TForm1 = class(TForm) Button1: TButton; procedure Button1Click(Sender: TObject); end; var Form1: TForm1; implementation {$R *.dfm} procedure Test(p: PChar); external 'Lib.dll'; var num: Integer; procedure TForm1.Button1Click(Sender: TObject); var p: PChar; begin Inc(num); p := StrAlloc(255); StrCopy(p, PChar(IntToStr(num))); Test(p); Text := p; StrDispose(p); end; end.调用的窗体文件:
object Form1: TForm1 Left = 0 Top = 0 Caption = 'Form1' ClientHeight = 103 ClientWidth = 173 Color = clBtnFace Font.Charset = DEFAULT_CHARSET Font.Color = clWindowText Font.Height = -11 Font.Name = 'Tahoma' Font.Style = [] OldCreateOrder = False PixelsPerInch = 96 TextHeight = 13 object Button1: TButton Left = 48 Top = 40 Width = 75 Height = 25 Caption = 'Button1' TabOrder = 0 OnClick = Button1Click end end