Object-C-NSDictionary

存储对象都必须是id(对象类型)不能使基础类型

NSDictionary *scores=[[NSDictionary alloc]initWithObjectsAndKeys:@"89",@"english",@"70",@"computer",nil];

*scores=[[NSDictionary alloc]initWithObjectsAndKeys:[NSNumber numberWithInt:89],@"english"];

scores=[NSDictionary dictionaryWithObjectsAndKeys:]用法与initWithObjectsAndKeys;

NSNumber *englishScore=[scores objectForKey:@"english"];

集合的遍历

方法一

for(NSString *key int socres)

{

    // 通过每个元素的key访问value

    NSLog(@"%@:%d",key,[[score objetForKey:key] intValue]);

}

方法二

[socres enumerateKeysAndObjectsUsingBloc:^(id key, id obj,BOOL *stop)

{

   NSNumber *num=(NSNumber *)obj;

    NSLog(@"%@:%d",key,[num intValue]);

}

方法三

NSArray *keysArray = [scores allKeys];

for(int i=0; i<[scores count]; i++)

{

     NSLog(@"%@:%d",[keysArray objectAtIndex:i);

NSLog(@"")----;

}

字典排序

NSArray *keysArray=[scores keysSortedByValueUsingSelector:@selector(compare:)];

Object-C-NSDictionary

原文：http://www.cnblogs.com/Opaser/p/4560155.html