【iOS学习笔记】Objective-C中根据函数名调用函数

原文出自：/article/2938533.html

Objective-C中调用函数的方法是“消息传递”，这个和普通的函数调用的区别是，你可以随时对一个对象传递任何消息，而不需要在编译的时候声明这些方法。所以Objective-C可以在runtime的时候传递消息。

主要用到：SEL和@selector，当然还有performSelector

看例子：

先是三个函数：

[cpp] view plaincopy

-(void)CallBack0

{

NSLog(@"CallBack0");

}

-(void)CallBack1:(int)a

{

NSLog(@"CallBack1:a=%i",a);

}

-(void)CallBack2:(int)a b:(int)b

{

NSLog(@"CallBack2:a=%i,b=%i",a,b);

}

performSelector调用：

[cpp] view plaincopy

[self performSelector:@selector(CallBack0)];

[self performSelector:@selector(CallBack1:) withObject:1];

[self performSelector:@selector(CallBack2:b:) withObject:1 withObject:2];

根据函数名动态调用：

[cpp] view plaincopy

NSString *a=@"CallBack0";

SEL faSelector=NSSelectorFromString(a);

[self performSelector:faSelector];

NSString *b=@"CallBack1:";

SEL fbSelector=NSSelectorFromString(b);

[self performSelector:fbSelector withObject:1];

NSString *c=@"CallBack2:b:";

SEL fcSelector=NSSelectorFromString(c);

[self performSelector:fcSelector withObject:1 withObject:2];

这样就可以根据函数名调用函数啦！