过滤UILable的特殊文字，重写setText

#import

//重写initialize

+ (void)initialize

{

    // 获取到UILabel中setText对应的method

    Method setText =class_getInstanceMethod([UILabel class], @selector(setText:));

    Method setTextMySelf =class_getInstanceMethod([self class],@selector(setTextHooked:));

    

    // 将目标函数的原实现绑定到setTextOriginalImplemention方法上

    IMP setTextImp =method_getImplementation(setText);

    class_addMethod([UILabelclass], @selector(setTextOriginal:), setTextImp,method_getTypeEncoding(setText));

    

   //然后用我们自己的函数的实现，替换目标函数对应的实现

    IMP setTextMySelfImp =method_getImplementation(setTextMySelf);

    class_replaceMethod([UILabelclass], @selector(setText:), setTextMySelfImp,method_getTypeEncoding(setText));

}

 

- (void)setTextHooked:(NSString *)string

{

    

   //在这里插入过滤算法

    string = [stringstringByReplacingOccurrencesOfString:@" " withString:@"\r\n"];

    

    // do something what ever youwant

    

    // invoke originalimplemention

    [selfperformSelector:@selector(setTextOriginal:) withObject:string];

}