NSDictionary，NSMutableDictionary 使用

NSDictionary

 

key --->value
索引 --->内容
存储键值对

 

（1）三种创建方式：

NSDictionary *dict = [NSDictionary dictionaryWithObject:@"Jony" forKey:@"name"];

　　

NSArray *keys = @[@"name", @"location"];
NSArray *objects = @[@"Jony", @"China"];
NSDictionary *dict = [NSDictionary dictionaryWithObject:objects forKey:keys];

 

NSDictionary *dict = @{@"name" : @"Jony", @"location", @"China"};

 

（2）调用

id obj = [dict objectForKey:@"name"];

id obj = dict[@"name"];

　　

NSMutableDictionary

NSMutableDictionary *dict = [NSMutableDictionary dictionary];

[dict setObject:@"Jony" forKey:@"name"];

//deleate
[dict removeObjectForKey:(id)];

NSMutableDictionary *dict = @{@"name" : @"Jony", @"location", @"China"};

　　

（1）字典遍历方式

NSArray *keys = [dict allKeys];

for (int i = 0; i < dict.count; i++)
{	
NSString *key = keys[i];
NSString *object = dict[key];

NSLog(@"%@ = %@", key, object);
}

　　

[dict enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop)]
{
NSLog(@"%@ -- %@", key, obj);

//Only oneTime
*stop = YES;
}

　　

Example：

NSArray *persons = @[
@{@"name" : @"Jony", @"location", @[@"China", @"Anhui"]},
@{@"name" : @"Jake", @"location", @"USA"},
@{@"name" : @"July", @"location", @"UK"},
@{@"name" : @"Jasson", @"location", @"Jepan"}
]

NSArray *location = persons[0][@"location"][0];