Objective-C：用数字验证文本字段

Question

我是iOS开发的新手。我想了解如何验证文本字段，如果它包含具有某些特定范围的数字，例如10表示联系号码？是否有可用的预定义功能？

谢谢。

Answer 1

+ (BOOL) validatePassword:(NSString *)passWord
{
   NSString *passWordRegex = @"^[a-zA-Z0-9]{6,20}+$";
   NSPredicate *passWordPredicate = [NSPredicate predicateWithFormat:@"SELF MATCHES %@",passWordRegex];
   return [passWordPredicate evaluateWithObject:passWord];
}

Answer 2

要让textfield只接受数字，只有10位数字才能使用此功能。

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string  {
   NSString *acceptedCharsters = @"0123456789";

 NSUInteger newLength = [textField.text length] + [string length] - range.length;
    return (newLength > 10) ? NO : YES;

NSCharacterSet *cs = [[NSCharacterSet characterSetWithCharactersInString:acceptedCharsters] invertedSet];

NSString *filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];

    return [string isEqualToString:filtered];


return YES;
}