如何排序NSPredicate

Question

我正在尝试使用NSPredicate对数组进行排序.我已经读过其他可能使用NSSortDescriptor的地方可能是一个选项.搞清楚这一点有些麻烦.

我试图通过companyName对数组进行排序.

任何建议表示赞赏,谢谢

格雷格

- (void)filterSummaries:(NSMutableArray *)all byNameThenBooth:(NSString*) text results:(NSMutableArray *)results
{
    [results removeAllObjects];

    if ((nil != text) && (0 < [text length])) {        
        if ((all != nil) && (0 < [all count])) {
            NSPredicate *predicate = [NSPredicate predicateWithFormat: @"companyName contains[cd] %@ OR boothNumber beginswith %@", text, text];
            [results addObjectsFromArray:[all filteredArrayUsingPredicate:predicate]];        
        }
    }
    else {
        [results addObjectsFromArray:all];
    }
}

Answer 1

你有几个选项如何排序数组:

我将在这里展示一个基于NSSortDescriptor的方法.

NSPredicate *predicate = [NSPredicate predicateWithFormat:
                                  @"companyName contains[cd] %@ OR boothNumber beginswith %@",
                                  text,
                                  text];

// commented out old starting point :)
//[results addObjectsFromArray:[all filteredArrayUsingPredicate:predicate]];

// create a descriptor
// this assumes that the results are Key-Value-accessible
NSSortDescriptor *descriptor = [NSSortDescriptor sortDescriptorWithKey:@"companyName" 
                                                             ascending:YES];
//
NSArray *results = [[all filteredArrayUsingPredicate:predicate]  
                     sortedArrayUsingDescriptors:[NSArray arrayWithObject:descriptor]];

// the results var points to a NSArray object which contents are sorted ascending by companyName key

这应该做你的工作.