Parse.com如何知道数组是否包含对象

Question

there is a method for PFQuery

PFQuery *query = [PFQuery queryWithClassName:@"class"];
[query whereKey:(NSString *)key containsAllObjectsInArray:(NSArray *)array];

is there similar method to define if there is NO specified object in array? like

[query whereKey:(NSString *)key doesNotContainAllObjectsInArray:(NSArray *)array];

If no, how to code this method by myself?

Answer 1

You can use the whereKey:notContainedIn: method for it.Please have a look at the documentation of Parse . Here's the sudo code from the link.

// Finds scores from anyone who is neither Jonathan, Dario, nor Shawn
NSArray *names = @[@"Jonathan Walsh",
                   @"Dario Wunsch",
                   @"Shawn Simon"];
[query whereKey:@"playerName" notContainedIn:names];

Answer 2

NSMutableArray *wantedObjects = [[NSMutableArray alloc] init];

[array enumerateKeysAndObjectsUsingBlock:^(id key, id obj, BOOL *stop) {
        if (/*do logic to match key or obj*/)
            [wantedObjects addObject:obj];
 }];

Now you can turn the above enumeration into a function. You can return [wantedObjects copy], which is an NSArray.

Answer 3

If you want to find objects where an Array key does not contain another object, you can simply use notEqualTo: as confirmed by a Parse developer here:

https://www.parse.com/questions/pfquery-not-include-any-object-in-array