ios NSDictionary\NSMutableDictionary

来源：互联网发布：软件开发的风险编辑：程序博客网时间：2024/05/16 07:55

NSDictionary是集合的一种，存储的是key和value，特点：key是唯一的,无序
使用：
1.初始化方式：

NSDictionary *dict = [NSDictionary dictionaryWithObject:@"jack" forKey:@"name"];        NSArray *keys = @[@"name", @"address"];        NSArray *values = @[@"rose", @"美国"];        NSDictionary *dict1 = [NSDictionary dictionaryWithObjects:values forKeys:keys];        NSDictionary *dict2 = [NSDictionary dictionaryWithObjectsAndKeys:@"15", @"age",                               @"crx", @"name",nil];        NSDictionary *dict3 = @{@"name" : @"jack", @"age" : @"18"};        id name = dict3[@"name"];        // 返回的是键值对的个数        NSLog(@"%ld", dict3.count);

2.NSMutableDictionary的使用

NSMutableDictionary *dict = [NSMutableDictionary dictionary];    //添加    [dict setObject:@"jack" forKey:@"name"];    [dict setObject:@"18" forKey:@"age"];    //删除    [dict removeObjectForKey:@"name"];    //修改    [dict setObject:@"20" forKey:@"age"];    //查找    id age = dict[@"age"];    NSLog(@"%@",age);

0 0