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按数字排序字典数组

[英]Sorting array of dictionaries by number

所以我有一个包含约180个字典的数组,每个字典中有5个对象(3个字符串和2个NSNumber)

我正在尝试通过其属性之一对每个字典进行排序,这对于字符串来说可以很好地工作,但是当涉及到数字时,它无法正确排序。

 -(void) sortArrayBy:(int)sortingNumber {

    switch (sortingNumber) {
            case 0:
                NSLog(@"sorting by atomicnumber");
                [self.elementsArray sortUsingDescriptors:[NSArray arrayWithObjects:
 // When sorting this comes back the same each time but not in the correct order
                [NSSortDescriptor sortDescriptorWithKey:@"ATOMIC NUMBER" ascending:YES], nil]];
                break;
            case 1:
                NSLog(@"sorting by name");
                [self.elementsArray sortUsingDescriptors:[NSArray arrayWithObjects: [NSSortDescriptor sortDescriptorWithKey:@"ELEMENT NAME" ascending:YES], nil]];
                break;
            case 2:
                NSLog(@"sorting by symbol");
                [self.elementsArray sortUsingDescriptors:[NSArray arrayWithObjects: [NSSortDescriptor sortDescriptorWithKey:@"CHEMICAL SYMBOL" ascending:YES], nil]];
                break;
            case 3:
                NSLog(@"sorting by mass");
 // When sorting this comes back the same each time but not in the correct order
                [self.elementsArray sortUsingDescriptors:[NSArray arrayWithObjects: [NSSortDescriptor sortDescriptorWithKey:@"ATOMIC MASS" ascending:YES], nil]];
                break;

            default:
                break;
        }

好的,所以我想出了问题,由于某种原因,它是按第一个数字而不是整个整数排序的,所以我使用以下代码:

        NSSortDescriptor *sortDescriptor = [NSSortDescriptor 

sortDescriptorWithKey:@"ATOMIC MASS" ascending:YES comparator:^(id obj1, id obj2) {
                return [obj1 compare:obj2 options:NSNumericSearch];
            }];

            [self.elementsArray sortUsingDescriptors:[NSArray arrayWithObjects: sortDescriptor, nil]];

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