如何创建 NSPredicate 来查找具有前导数值的条目？
我正在使用 NSPredicates 根据名称属性获取实体。为以字母开头的名称创建谓词很容易（@“name BEGINSWITH %@”，searchLetter），但是现在我想获取名称以数字值（或更确切地说是非字母字符）开头的所有实体。
这里合适的谓词表达式是什么？
现在我不想太深入谓词编程，因为这就是我现在所需要的，而且时间过得真快。所以，请不要向我指出谓词编程指南，我只需要那个表达式..:)
非常感谢大家！
I'm using NSPredicates to fetch entities based on a name attribute. Creating a predicate for names beginning with letters was easy (@"name BEGINSWITH %@", searchLetter), however now I'd like to fetch all entities with a name that begins with a numerical value, or rather a non-alphabetical character.
What would be the appropriate predicate expression here?
Right now I don't want to get too deep into predicate programming, as this is all I need right now and time flies. So, please, don't point me to the Predicate Programming Guide, I just need that expression.. :)
Thanks alot guys!
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如果 MATCHES 运算符不适用于获取请求，那么您实际上必须手动执行操作：
这将获取不以字母开头的所有内容。同样：
将获得以数字开头的所有内容。
编辑评论引发了另一个想法：
如果您可以提取
name的第一个字母，您可以这样做：（name[0]是name的第一个字符，并且arrayOfLetters是字母字符的NSArray）If the
MATCHESoperator doesn't work with a fetch request, then you'll essentially have to do stuff manually:That would get everything that does not start with a letter. Likewise:
Would get everything that does start with a number.
edit the comment prompted another idea:
If you could extract the first letter of the
name, you could do:(
name[0]being the first character ofname, andarrayOfLettersbeing anNSArrayof the alphabetic characters)您可以使用“匹配”，其中可以使用任何正则表达式（例如 ^[0-9]）进行比较。但据我所知，这在处理核心数据时不起作用。
另一个解决方案是使用新的 (OS X 10.6, iOS 4.0)
predicateWithBlock:并使用字符串方法自行检查条件。You can use 'MATCHES' where you can use any regex (e.g. ^[0-9]) to compare. But as far as I know that does not work when dealing with Core Data.
Another soluton would be to use the new (OS X 10.6, iOS 4.0)
predicateWithBlock:and check the condition yourself with string methods.