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]);
}
}
}