使用正则表达式限制输入字符为中文、英文、数字

NSString *regex = @"[0-9a-zA-Z\\u4e00-\\u9fa5]+$";

NSPredicate *pred = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", regex];

if (![pred evaluateWithObject:textView.text]) {

[SVProgressHUD showInfoWithStatus:@"标签只能由中文、英文、数字组成"];

}