Objective－C 字典："NSDictionary" 和 "NSMutableDictionary"

#import <Foundation/Foundation.h>

int main(int argc, const char * argv[]) {
    @autoreleasepool {

        /*--------------------  NSDictionary  ---------------------*/
        //value在前,key 在后,value 和 key 要成双出现
        //注意：在字典中键值是无序的



        //创建一个空的字典
        NSDictionary *dictionary1 = [[NSDictionary alloc] init];
        NSDictionary *dictionary2 = [NSDictionary dictionary];

        //创建一个键值对的字典
        NSDictionary *dictionary3 = [NSDictionary dictionaryWithObject:@"1" forKey:@"One"];
        NSLog(@"dictionary3 = %@",dictionary3);

        //创建多个键值对的字典
        NSDictionary *dictionary4 = [NSDictionary dictionaryWithObjectsAndKeys:@"1",@"a",@"2",@"b",@"3",@"c", nil];
        NSLog(@"dictionary4 = %@",dictionary4);

        NSDictionary *dictionary5 = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"11",@"22",@"33", nil] forKeys:[NSArray arrayWithObjects:@"aa",@"bb",@"cc", nil]];
        NSLog(@"dictionary5 = %@",dictionary5);

        //根据一个字典创建一个新的字典
        NSDictionary *dictionary6 = [NSDictionary dictionaryWithDictionary:dictionary5];
        NSLog(@"dictionary6 = %@",dictionary6);

        //本地读取字典
        NSDictionary *dictionary7 = [NSDictionary dictionaryWithContentsOfFile:@""];

        //从网络读取字典
        NSDictionary *dictionary8 = [NSDictionary dictionaryWithContentsOfURL:[NSURL URLWithString:@""]];

        //键值对的数量
        NSUInteger count = [dictionary5 count];
        NSLog(@"count = %lu",count);

        //通过key来访问字典的值
        NSDictionary *dictionary9 = [dictionary5 objectForKey:@"aa"];
        NSLog(@"dictionary9 = %@",dictionary9);

        //通过key来访问字典的值   新语法
        NSDictionary *dictionary10 = dictionary5[@"bb"];
        NSLog(@"dictionary10 = %@", dictionary10);


        //如何得到key的值
        NSArray *keysArray = dictionary5.allKeys;
        NSLog(@"keysArray1 = %@",keysArray);

        //如何得到value的值
        NSArray *valuesArray = dictionary5.allValues;
        NSLog(@"valuesArray = %@",valuesArray);


        //遍历字典中的所有的值

        //用for循环
        for (int i = 0; i < valuesArray.count; i++) {
            NSLog(@"%@ = %@",keysArray[i], dictionary5[keysArray[i]]);
        }


        //用 fori 快速枚举
        for (NSString *key in dictionary5) {
            NSLog(@"key = %@    value = %@", key, dictionary5[key]);
        }


        //使用枚举器遍历
        NSEnumerator *enumrator = [keysArray objectEnumerator];
        NSString *key;
        while (key = [enumrator nextObject]) {
            NSLog(@"%@ = %@",key, dictionary5[key]);
        }


        //在不可变字典中不能存储相同的key，如果相同的key，则只会答应一个key对应的value
        NSDictionary *dictionary = [NSDictionary dictionaryWithObjectsAndKeys:@25,@"age",@"GZ",@"address",@"Rick",@"name",@"Jack",@"name", nil];
        for (NSString *key in [dictionary allKeys]) {
            NSLog(@"%@ = %@", key, dictionary[key]);
        }


        /*-------------------   NSMutableDictionary    ---------------------*/

        //初始化方法  创建一个又一个键值对的可变字典
        NSMutableDictionary *mDictionary1 = [NSMutableDictionary dictionaryWithObject:@"zyx" forKey:@"name"];

        //创建多个可变字典
        NSMutableDictionary *mDictionary2 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"zyx",@"name",@23,@"age",@"GZ",@"address", nil];
        NSLog(@"mDictionary = %@",mDictionary2);

        //通过另一个字典创建一个字典
        NSMutableDictionary *mDictionary3 = [NSMutableDictionary dictionaryWithDictionary:mDictionary2];
        NSLog(@"mDictionary3 = %@",mDictionary3);



        //NSArray *array = mDictionary2.allKeys;
        NSEnumerator *enumerator = [[mDictionary3 allKeys] objectEnumerator];
        NSString *key1;
        while (key1 = [enumerator nextObject]) {
            NSLog(@"%@ = %@",key1, mDictionary3[key1]);
        }


        //枚举器
        NSEnumerator *enumerator2 = [[mDictionary2 allKeys] objectEnumerator];
        NSString *key2;
        while (key2 = [enumerator2 nextObject]) {
            NSLog(@"%@ = %@",key2 ,mDictionary2[key2]);
        }

        //可变字典独有初始化方法   创建了初始为10个键值对的可变字典，只是初始的大小，提高程序效率。并没有限制字典的大小，如果继续添加数据，字典元素个数会继续增加
        NSMutableDictionary *mDictionary4 = [NSMutableDictionary dictionaryWithCapacity:10];

        //操作字典
        //增
        [mDictionary4 setValue:@"zyx1" forKey:@"name1"];
        [mDictionary4 setValue:@"zyx2" forKey:@"name2"];
        [mDictionary4 setValue:@"zyx3" forKey:@"name2"];//(如果原来字典中有了Key这个关键字，这次新加Key，就会覆盖原来的Key)
        //新语法
        mDictionary4[@"name4"] = @"zyx4";
        NSLog(@"mDictionary4 = %@",mDictionary4);

        //删除指定key的对象
        [mDictionary4 removeObjectForKey:@"name1"];
        NSLog(@"%@",mDictionary4);

        //删除全部
        [mDictionary4 removeAllObjects];
        NSLog(@"%@",mDictionary4);


        //例子
        NSMutableDictionary *mDictionary5 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"zyx",@"name1",@22,@"age",@"GZ",@"address",@"zyx",@"name2",@"zyx",@"name3", nil];

        NSEnumerator *enumerator3 = [[mDictionary5 allKeys] objectEnumerator];
        NSString *key3 ;

        while (key3 = [enumerator3 nextObject]) {
            NSLog(@"%@ = %@",key3, mDictionary5[key3]);
        }

        NSArray *key5 = mDictionary5.allKeys;
        for (NSString *key in key5) {
            NSString *string = mDictionary5[key];
            if ([string isEqual:@"zyx"]) {
                NSLog(@"key = %@",key);
            }
            //NSLog(@"%@ = %@",key, mDictionary5[key]);
        }

    }
    return 0;
}