ios - 按数字对字典数组进行排序

Question

所以我有一个包含大约 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）

我正在尝试按其属性之一对每个字典进行排序，这对字符串很好，但是当涉及到数字时，它不能正确排序。

 -(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;
        }

Answer 1

好的，所以我发现了问题，由于某种原因，它是按第一个数字而不是整数排序的，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]];