Question

i have a uitextfield and i am validating text field and the validation is adding “-“(hypen)for every 3 numbers. and it is working fine

and the code is as follows
but now i want to change the validation in such a way that to restrict no of characters to 10 and adding “-” after 3rd and 7th place dynamically while entering and editing
[ex:123-456-7890] it should be done while editing also…

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {

NSString *separator = @"-";
int seperatorInterval = 3;
NSString *originalString = [textField.text stringByReplacingOccurrencesOfString:separator withString:@""];

if (![originalString isEqualToString:@""] && ![string isEqualToString:@""]) {

    NSString *lastChar = [textField.text substringFromIndex:[textField.text length] - 1];
    int modulus = [originalString length] % seperatorInterval;

    if (![lastChar isEqualToString:separator] && modulus == 0) {

        textField.text = [textField.text stringByAppendingString:separator];
    }
}

return YES;

}
but now i want to change the validation in such a way that to restrict no of characters to 10 and adding “-” after 3rd and 7th place dynamically while entering and editing
[ex:123-456-7890]
it should be done while editing also…

Answer 1

You just need to add this block of code to the bottom of your function you have shown here.

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {


    if ([textField isEqual:textField]  ) {
    NSUInteger newLength = [textField.text length] + [string length] - range.length;
    return (newLength > 10) ? NO : YES; //the 10 here represents the MAX allowed characters in the text field. So you may want to increase it to 12 if you are going to have 2 "-"s 

    }
}