OC语言学习06-字典对象

// NSDictionary

//创建不可变字典对象

//字典对象中的元素都是键值对

//key:value

//字典中的元素没有顺序

//NSMutableDictionary

//创建可变字典对象，继承于NSDictionary;

//可以使用所有的不可变字典类中的方法

//对于可变字典对象，可以进行添加修改删除操作

#import <Foundation/Foundation.h>

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

    @autoreleasepool {

        //创建一个不可变对象

        NSDictionary *dict =@{@"one":@"1",@"two":@"2",@"three":@"3",@"four":@"4"};

        NSLog(@"%@", dict);

    }

    

    //用出入的键值对创建字典对象

    NSDictionary *dict1 = [[NSDictionaryalloc] initWithObjectsAndKeys:@"9",@"nine",@"8",@"eight",@"7",@"seven",nil];

    NSLog(@"dict1 = %@", dict1);

    

     //

    NSDictionary *dict2 = [[NSDictionaryalloc] initWithDictionary:dict1];

    NSLog(@"dict2 = %@",dict2);

    

    //类方法创建字典对象

    //创建空的字典对象

    NSDictionary *dict5 = [NSDictionarydictionary];

    NSLog(@"%@", dict5);

    

    NSDictionary *dict6 = [NSDictionarydictionaryWithObjectsAndKeys:@"5",@"five",@"6",@"six",@"7",@"seven",nil];

    NSLog(@"dict6 = %@", dict6);

    

    NSDictionary *dict7 = [NSDictionarydictionaryWithDictionary:dict2];

    NSLog(@"dict7 = %@", dict7);

    

    NSInteger count = [dict1count];

    NSLog(@"count = %li", count);

    //通过Key获取字典中Key对应的值

    id obj = [dict1objectForKey:@"seven"];

    NSLog(@"obj = %@", obj);

    

    //获取所有的key

    NSArray *keyArray = [dict1allKeys];

    NSLog(@"keyArray = %@", keyArray);

    

    //获取所有的值

    NSArray *valueArray = [dict1allValues];

    NSLog(@"valueArray = %@", valueArray);

    

    //判断两个字典对象是否相等

    BOOL ret = [dict1isEqualToDictionary:@{@"one":@"1",@"two":@"2",@"three":@"3"}];

    

    if(ret) {

        NSLog(@"字典对象相等");

    }

    else {

        NSLog(@"字典对象不相等");

    }

    

    //字典的遍历

    //枚举器法

    NSEnumerator *keyEnumerator = [dict1keyEnumerator];

    id obj2 =nil;

    while (obj2 = [keyEnumeratornextObject]) {

        NSLog(@"key = %@ value = %@", obj2, [dict1objectForKey:obj2]);

    }

    

    //快速枚举法

    for(id obj3in dict1) {

        NSLog(@"快速枚举法：key = %@ value = %@", obj3, [dict1 objectForKey:obj3]);

    }

    

    return0;

}