objective-c - Obtain array objects with specific value

Question

What I want to do is to return the NSArray objects of a specific value (numbers). How can I do it?

Thanks in Advance

Answer 1

您可以indexesOfObjectsPassingTest:在您的NSArray实例上使用。

NSArray *array = @[1, 2, 3];

typedef BOOL (^Predicate)(id obj, NSUInteger idx, BOOL *stop);
Predicate predicate = ^(id obj, NSUInteger idx, BOOL *stop) {
    if ([obj isKindOfClass:[NSNumber class]]) {
        *stop = YES;
        return YES;
    } else return NO;
};

NSIndexSet *indexes = [array indexesOfObjectsPassingTest:predicate];

https://developer.apple.com/library/mac/documentation/Cocoa/Reference/Foundation/Classes/NSArray_Class/NSArray.html#//apple_ref/doc/uid/20000137-SW24