procedure TForm1.btn1Click(Sender: TObject); var tmp: Integer; begin tmp := StrToInt(edt1.Text); if (tmp mod 2 = 0) then begin MessageBox(0, PAnsiChar(IntToStr(tmp)+' 为偶数'), '提示', MB_OK) end else begin MessageBox(0, PAnsiChar(IntToStr(tmp)+' 为奇数'), '提示', MB_OK) end; end;
//判断奇数偶数
procedure TForm1.btn1Click(Sender: TObject); var tmp: Integer; begin tmp := StrToInt(edt1.Text)+StrToInt(edt2.Text); edt3.Text := IntToStr(tmp); end; //把两数相加并把结果放到第三个文本框内
procedure TForm1.btn1Click(Sender: TObject); var tmp: Double; begin tmp := StrToFloat(edt1.Text)+StrToFloat(edt2.Text); edt3.Text := FloatToStr(tmp); end; //上面的只能计算整数 这个可以计算小数 //double 转 string 和 string 转 double
//自定义函数 返回两个数字中较大的 function Max(x, y: Real): Real; begin if x > y then result := x else result := y; end; //注意 if x > y then result := x 后不能有 ; 号
DLL窗体
//----------------------dpr 部分 library Project1; uses Forms, DllFormUnit in 'DllFormUnit.pas' {Form1}; {$R *.res} exports UppTolow; end. //----------------------------pas部分 unit DllFormUnit; interface uses Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms, Dialogs; type TForm1 = class(TForm) private { Private declarations } public { Public declarations } end; var Form1: TForm1; function UppToLow: Boolean; stdcall; implementation {$R *.dfm} function UppToLow: Boolean; var Form1: TForm1; begin result:=False; Form1:=TForm1.Create(Application); Form1.ShowModal; end; end. //----------------------------调用声明 function UppToLow:Boolean;stdcall external 'Project1.dll'; implementation {$R *.dfm} //----------------------------按钮调用 procedure TMainForm.btn2Click(Sender: TObject); begin UppToLow; end;
//DLL自动呼出窗体 library Project1; uses Forms, DllFormUnit in 'DllFormUnit.pas' {Form1}; {$R *.res} exports UppTolow; begin UppTolow; end.
//DLL编写 library Test; uses SysUtils, Classes, Dialogs; function Test11(a, b: integer): integer; begin Result := a + b; ShowMessage('Test11函数调用'); end; exports Test11; begin ShowMessage('DLL启动函数调用'); end.
//Delphi调用汇编指令 procedure sitCall();stdcall; begin //// [[[[[95E800+1c]+24]+918]+14]+1c ] asm push 1 mov ecx,$95E800 add ecx,$1C mov ecx,[ecx] // ecx=Pointer(ecx^) add ecx,$24 // ecx=ecx+$24 mov ecx,[ecx] add ecx,$918 mov ecx,[ecx] add ecx,$14 mov ecx,[ecx] add ecx,$1C mov ecx,[ecx] mov ebx,$452b20 call ebx end; end;