NSMutableArray 排序 - 不区分大小写

Question

我将NSMutableArray 排序如下：

    NSSortDescriptor *sortDescriptor;
    sortDescriptor = [[[NSSortDescriptor alloc] initWithKey:str_key ascending:bool_asc_desc] autorelease];
    NSArray *sortDescriptors = [NSArray arrayWithObject:sortDescriptor];
    NSArray *sortedArray;
    sortedArray = [ads_printers_array sortedArrayUsingDescriptors:sortDescriptors];

问题是它区分大小写，我想让它不区分大小写。我怎样才能做到这一点？我尝试阅读文档并发现如下内容：

sortDescriptor = [[[NSSortDescriptor alloc] initWithKey:str_key ascending:bool_asc_desc selector: @selector(caseInsensitiveCompare)] autorelease];

但是，我不知道应该在选择器参数中添加什么。谢谢！

Answer 1

对于 Swift，请执行以下操作：

let sortDescriptor = NSSortDescriptor(key: sortDescriptorKey, ascending: true, selector: #selector(NSString.caseInsensitiveCompare(_:)))

Answer 2

NSSortDescriptor *sortDescriptor = [[NSSortDescriptor alloc] initWithKey:str_key 
    ascending:YES selector:@selector(caseInsensitiveCompare:)];

ads_printers_array = [ads_printers_array sortedArrayUsingDescriptors:[NSArray 
    arrayWithObject:sortDescriptor]];