//
// main.m
// OC05-task-01
//
// Created by Xin the Great on 15-1-25.
// Copyright (c) 2015年 Xin the Great. All rights reserved.
//
#import
#import "NSArray+Log.h"
int main(int argc, const char * argv[]) {
@autoreleasepool {
// insert code here...
////////////////NSDictionary--字典///////////////////
//初始化一个字典
//注意：字典里面所装数据类型：对象，不可以是基本数据类型
//字典是无序的
//key 通常是字符串， key必须唯一
NSDictionary *dic = [[NSDictionary alloc] initWithObjectsAndKeys:
@"value",@"key",
@"value1",@"key1", nil];
NSLog(@"dic is %@",dic);
//创建一个数组
NSArray *names = @[@"张三", @"李四", @"王五"];
NSLog(@"names is %@", names);
NSDictionary *dic2 = [NSDictionary dictionaryWithObjectsAndKeys:
@"v1",@"k1",
@"v2",@"k2",
@"v3",@"k3",
names,@"k4",nil];
NSLog(@"dic2 is %@", dic2);
//从字典中取出value,如果这个字典不存在这个key， 则返回null
NSString *str = [dic2 objectForKey:@"k1"];
NSLog(@"str is %@",str);
NSArray *dArr = [dic2 objectForKey:@"k4"];
NSLog(@"dArr is %@", dArr);
NSString *str1 = [dic2 objectForKey:@"k5"];
NSLog(@"str is %@",str1);
//字典中键值对的个数
NSUInteger count = [dic2 count];
NSLog(@"count is %ld",count);
//获取字典中所有的key
NSArray *keys = [dic2 allKeys];
NSLog(@"keys is %@",keys);
//获取所有的Value
NSArray *values = [dic2 allValues];
NSLog(@"values is %@",values);
//从字典中取出names的第一个元素
// NSArray *arr = [dic2 objectForKey:@"k4"];
// NSString *name1 = [arr objectAtIndex:0];
//嵌套调用
NSString *name1 = [[dic2 objectForKey:@"k4"] objectAtIndex:0];
NSLog(@"name1 is %@", name1);
//字典的快速创建和取值方法
NSDictionary *dic3 = @{@"k1":@"v1",
@"k2":@"v2",
@"k3":@"v3"};
id str2 = dic3[@"k1"];
NSLog(@"str2 is %@",str2);
}
return 0;
}