[Delphi]过程Procedure动态调用

过程也可以像通用变量一样声明、调用

 

procedure HelloWorld;

begin  

ShowMessage('HI');

end;

procedure HelloWorld2(a:String);

begin  

ShowMessage('HI');

end;

 

procedure TFormSplash.FormCreate(Sender: TObject);

var 

    myproc:Procedure; 

   myproc2:Procedure(a:String);

begin   

    myProc:=HelloWorld;

   if Assigned(myProc) then  myProc;

   myproc2:= HelloWorld2;

   if Assigned(myproc2) then  myproc2('');

 

 

也可以这样定义

 var 

    myproc:Procedure=HelloWorld;

   myproc2:Procedure(a:String)=HelloWorld2;

 

参数类型不同或顺序不同会提示

  E2009 Incompatible types: ‘Parameter lists differ’

直接赋值 对象中的过程或函数将出错

 E2009 Incompatible types: ‘regular procedure and method pointer’

需要在Type里声明类型

type

  TMethod = procedure of object;

  TFunc = function: integer of object;

  TNotifyEvent = procedure(Sender: TObject) of object;