Foundation之NSDictionary
一、NSDictionary的使用
1 int main(int argc, const char * argv[]) 2 { 3 4 @autoreleasepool { 5 6 // 创建方式一 7 NSDictionary *dict1 = [NSDictionary dictionaryWithObjectsAndKeys: 8 @"value1", @"key1", 9 @"value2", @"key2", nil]; 10 NSLog(@"%@", dict1); 11 // 创建方式二 12 NSDictionary *dict2 = [NSDictionary dictionaryWithObjects:[NSArray arrayWithObjects:@"value1", @"value2", nil] forKeys:[NSArray arrayWithObjects:@"key1", @"key2", nil]]; 13 NSLog(@"%@", dict2); 14 15 // 获取键值对个数 16 NSLog(@"%zi", [dict2 count]); 17 // 根据key获取value 18 NSLog(@"%@", [dict2 objectForKey:@"key1"]); 19 20 // 遍历所有key 21 for (id key in dict2) { 22 NSLog(@"%@", [dict2 objectForKey:key]); 23 } 24 25 26 } 27 return 0; 28 }