BOOL result1 = [err caseInsensitiveCompare:@"7B"]==NSOrderedSame;// 不区分大小写比较
Returns the result of invoking compare:options: with NSCaseInsensitiveSearch as the only option.
This method is the equivalent of invoking compare:options:with NSCaseInsensitiveSearchas the only option.
原文：http://www.cnblogs.com/dengchaojie/p/7794344.html