字典

//创建不可变字典对象

NSDictionary *dic = [[NSDictionary alloc] initWithObjectsAndKeys:@”1”,@”2”,@”3”,@”4”,@”5”,@”6”,nil];

NSLog(@”%@”,dic);

// 计算键值对数量

NSLog(@”%ld”,dic.count);

// 通过key找到对应的value

NSLog(@”%@”,[dic objectForKey:@”2”]);

// dic[对应的key]

NSLog(@”%@”,dic[@”2”]);

// 获取所有的key和value

NSLog(@”%@”,dic.allKeys);

NSLog(@”%@”,dic.allValues);

// 可变字典对象
// 空字典
NSMutableDictionary *dic1 = [NSMutableDictionary dictionary];
NSMutableDictionary *dic2 = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"1",@"2",@"3",@"4",nil];
// 遍历字典

for (NSString *strin dic2) {

NSLog(@”%@ %@”,str,dic2[str]);

}

NSMutableDictionary *dic = [NSMutableDictionary dictionaryWithObjectsAndKeys:@"1",@"2",@"3",@"4",@"5",@"6",nil];
// 对可变字典添加
[dic setObject:@"7" forKey:@"8"];
// 对可变字典修改
[dic setObject:@"10" forKey:@"2"];
NSLog(@"%@",dic);

// 移除指定键值对
[dic removeObjectForKey:@"4"];
// 全部移除
[dic removeAllObjects];

字典和数组的嵌套

字典里嵌套数组
NSArray *arr1 =@[@"1",@"2",@"3",@"4"];
NSArray *arr2 =@[@"5",@"6",@"7",@"8"];
NSMutableDictionary *dic = [NSMutableDictionary dictionaryWithObjectsAndKeys:arr1,@"arr1", arr2,@"arr2",nil];
// 遍历

for (NSString *strin dic) {

NSArray *arr = dic[str];

for (NSString *tempin arr) {

NSLog(@”%@”,temp);

}

}

数组中嵌套字典
NSDictionary *dic1 = [NSDictionary dictionaryWithObjectsAndKeys:@"杨林",@"name",@"19",@"age",nil];
NSDictionary *dic2 = [NSDictionary dictionaryWithObjectsAndKeys:@"刘山山",@"name",@"20",@"age",nil];
NSDictionary *dic3 = [NSDictionary dictionaryWithObjectsAndKeys:@"商帅",@"name",@"21",@"age",nil];
NSArray *arr =@[dic1,dic2,dic3];
// 遍历

for (NSDictionary *dicin arr) {

for (NSString *strin dic) {

NSLog(@”%@”,dic[str]);

}

}

// 三层嵌套
NSDictionary *dic1 = [NSDictionary dictionaryWithObjectsAndKeys:@"杨林",@"name",@"19",@"age",nil];
NSDictionary *dic2 = [NSDictionary dictionaryWithObjectsAndKeys:@"刘山山",@"name",@"20",@"age",nil];
NSDictionary *dic3 = [NSDictionary dictionaryWithObjectsAndKeys:@"商帅",@"name",@"21",@"age",nil];
NSArray *arr1 =@[dic1,dic2];
NSArray *arr2 =@[dic3];
NSDictionary *bigDic = [NSDictionary dictionaryWithObjectsAndKeys:arr1,@"arr1",arr2,@"arr2",nil];
// 遍历

for (NSString *strin bigDic) {

NSMutableArray *arr = bigDic[str];

for (NSMutableDictionary *dicin arr) {

for (NSString *keyin dic) {

NSLog(@”%@”,dic[key]);

}

}

}

//三层嵌套

NSDictionary *dic1 = [NSDictionary dictionaryWithObjectsAndKeys:@”杨林”,@”name”,@”19”,@”age”,nil];

NSDictionary *dic2 = [NSDictionary dictionaryWithObjectsAndKeys:@”刘山山”,@”name”,@”20”,@”age”,nil];

NSDictionary *dic3 = [NSDictionary dictionaryWithObjectsAndKeys:@”商帅”,@”name”,@”21”,@”age”,nil];

NSArray *arr1 =@[dic1,dic2];

NSArray *arr2 =@[dic3];

NSArray *bigArr =@[arr1,arr2];

//遍历

for (NSArray *arrin bigArr) {

for (NSDictionary *dicin arr) {

for (NSString *strin dic) {

NSLog(@”%@”,dic[str]);

}

}

}