NSDictionary

       //字典都是一个key 对应一个 value
        NSDictionary *d = [NSDictionary dictionaryWithObject:@"lxc" forKey:@"name"];
        
        //字典的排列是无序排列，这点和数组不同数组是有序排列
        NSDictionary *d1 = [NSDictionary dictionaryWithObjects:@[@"lxc",@"23",@"178"] forKeys:@[@"name",@"age",@"height"]];
        
        //快速创建字典
        NSDictionary *dd = @{@"name":@"cyf"};
        NSLog(@"%@",dd);
        NSDictionary *d11 = @{@"name":@"cyf",@"age":@"22",@"height":@"155"};
        NSLog(@"%@",d11);
        //字典文件写入
        [d11 writeToFile:@"/Users/liuxingchen/Desktop/test.plist" atomically:YES];
        //字典文件读取
        NSDictionary *dict = [NSDictionary dictionaryWithContentsOfFile:@"/Users/liuxingchen/Desktop/test.plist"];
        //用for i 遍历字典
        for (int i = 0; i< d1.count; ++i) {
            NSArray *keys = [d1 allKeys];
            NSString *key = keys[i];
            NSString *value = d1[key];
            NSLog(@"%@ = %@",key,value);
        }
        //用for in 遍历字典
        for (NSString *key in d11) {
            NSString *value = d11[key];
            NSLog(@"%@ = %@",key,value);
        }
        //用OC迭代器遍历字典
        [d11 enumerateKeysAndObjectsUsingBlock:^(id  _Nonnull key, id  _Nonnull obj, BOOL * _Nonnull stop) {
            NSLog(@"%@ = %@",key,obj);
        }];
//字典写入
        [dict writeToFile:@"/Users/yao/Desktop/test.plist"atomically:YES];
        //字典读取
        NSDictionary *dic = [NSDictionary dictionaryWithContentsOfFile:@"/Users/yao/Desktop/test.plist"];
    };