Objective-C中NSNumber与NSDictionary的用法简介

void number() { 
    // 将int类型的10 包装成 一个NSNumber对象 
    NSNumber *number = [NSNumber numberWithInt:10]; 
    NSLog(@"number=%@", number); 
     
    NSMutableArray *array = [NSMutableArray array]; 
    // 添加数值到数组中 
    [array addObject:number]; 
     
    // 取出来还是一个NSNumber对象，不支持自动解包(也就是不会自动转化为int类型) 
    NSNumber *number1 = [array lastObject]; 
     
    // 将NSNumber转化成int类型 
    int num = [number1 intValue]; 
    NSLog(@"num=%i", num); 
} 

NSArray * skyAArrays = [NSArray arrayWithObjects:@"A天空1号",@"A天空2号",@"A天空3号",nil];
    NSArray * skyBArrays = [NSArray arrayWithObjects:@"B天空1号",@"B天空2号",@"B天空3号",nil];
    NSArray * skyCArrays = [NSArray arrayWithObjects:@"C天空1号",@"C天空2号",@"C天空3号",nil];
   
    // NSArray * skyArray = [NSArray arrayWithObjects:skyAArrays,skyBArrays,skyCArrays, nil];
   
   //字典中所有的key
    NSArray * keys = [NSArray arrayWithObjects:@"name",@"sex",@"age",nil];
   //字典中所有跟key对应的value
    NSArray * values = [NSArray arrayWithObjects:@"liuhui",@"男",[NSNumbernumberWithInt:36],nil];
   //创建字典对象方法1
    NSDictionary * myDic = [[NSDictionary alloc]initWithObjects:values forKeys:keys];
    NSLog(@"my dic = %@",myDic);
   // 创建字典对象方法2    
    NSDictionary * yourDic = [[NSDictionary alloc] initWithObjectsAndKeys:skyAArrays,@"A",skyBArrays,@"B",skyCArrays,@"C",nil];
    NSLog(@"your dic = %@",yourDic);
    
    NSLog(@"%@",[yourDic objectForKey:@"A"]);
    // - (NSArray *)allKeys; 返回的是 NSArray类型,方便用 objectAtIndex取出一个个key
    NSLog(@"%@",[yourDic allKeys]);
    NSLog(@"%@",[yourDic allValues]);
   
   //添加数据(setObject 一般没有一种key才添加,有同名的key而用这种方法,会覆盖掉)，注意：id key  是成对出现的 
    [mutableDictionary setObject:@"good lucky"forKey:@"why"]; 
    [mutableDictionary setObject:@"bye bye" forKey:@"how"]; 

   //删除指定键值的数据 
    [mutableDictionary removeObjectForKey:..]; 
   //删除所有数据 
    [mutableDictionary removeAllObjects]; 

    //字典的普通遍历(无序)
    for (int i =0; i < [yourDic count]; i++) {    
        NSLog(@"key = value <====> %@ = %@",[[yourDic allKeys] objectAtIndex:i],[yourDic objectForKey:[[yourDic allKeys]objectAtIndex:i]]);
    }
   
    // 字典的快速遍历 取出来的obj一定是key
    for (id obj in yourDic) {   
        NSLog(@"%@",obj);
        id value = [yourDic objectForKey:obj];  
        NSLog(@"%@",value);
    }