//要点13: 需要给其他单元调用, 必须在 interface 声明, 但必须在 uses 区后面 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; {需要给其他单元调用, 必须在 interface 声明, 但必须在 uses 区后面} function MyFun(x,y: Integer): Integer; {函数声明} var Form1: TForm1; implementation {$R *.dfm} function MyFun(x,y: Integer): Integer; {函数实现} begin Result := x + y; end; procedure TForm1.Button1Click(Sender: TObject); var i: Integer; begin i := MyFun(1,2); ShowMessage(IntToStr(i)); {3} end; end.