// // main.m // nsDictionary // // Created by syrcfwzx on 16/1/8. // Copyright (c) 2016年 syrcfwzx. All rights reserved. // #import <Foundation/Foundation.h> int main(int argc, const char * argv[]) { @autoreleasepool { //注意key 通常是字符串对象 NSMutableDictionary* dic = [[NSMutableDictionary alloc]initWithObjectsAndKeys:@"jay",@"name",@"22",@"age",@"f",@"gender", nil]; NSLog(@"%@",dic); NSDictionary* dic1 = [NSDictionary dictionaryWithObject:@"166" forKey:@"height"]; [dic addEntriesFromDictionary:dic1]; NSLog(@"%@",dic); [dic setObject:@"66" forKey:@"weight"]; NSLog(@"%@",dic); //遍历 //1.先找到所有的key 2计算key的个数 NSArray* array = [dic allKeys]; NSInteger count = [dic count]; for(int i = 0;i<count;i++) { id key = [array objectAtIndex:i]; NSLog(@"%@",[dic objectForKey:key]); } //for in语法 for(id key in array) { id obj=[dic objectForKey:key]; NSLog(@"%@",obj); } //block遍历 [dic enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) { NSLog(@"key=%@ obj=%@",key,obj); }]; //3通过枚举对象进行枚举 //将字典里的key转成枚举对象 用于遍历 NSEnumerator* enumerator = [dic keyEnumerator]; id key; while (key=[enumerator nextObject]) { id obj3 = [dic objectForKey:key]; NSLog(@"%@",obj3); } } return 0; }