NSPredicate for mobile number validation - ios

Question

How to validate a phone number (NSString *) by NSPredicate?
Rules:
minimum 10 digits
maximum 10 digits
the first digit must be 7,8 or 9
Thanks

Answer 1

An NSPredicate based on a regular expression will fit your requirements.
NSString *stringToBeTested = #"8123456789";
NSString *mobileNumberPattern = #"[789][0-9]{9}";
NSPredicate *mobileNumberPred = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", mobileNumberPattern];
BOOL matched = [mobileNumberPred evaluateWithObject:stringToBeTested];
You don't need to keep the pattern in a string by itself, but regexes are complicated enough already so it makes the overall code clearer if you keep it out of the NSPredicate format string.

Answer 2

You can just use below code
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string; // return NO to not change text
{
if(textField.tag == 111)
{
if([self MobileNumberValidate:string] == TRUE)
return YES;
else
return NO;
}
return YES;
}
#pragma mark - Mobile Number validation
- (BOOL)MobileNumberValidate:(NSString*)number
{
NSString *numberRegEx = #"[0-9]";
NSPredicate *numberTest = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", numberRegEx];
if ([numberTest evaluateWithObject:number] == YES)
return TRUE;
else
return FALSE;
}

Answer 3

NSString *phoneNumber = #"1234567890";
NSString *phoneRegex = #"[789][0-9]{3}([0-9]{6})?";
NSPredicate *test = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", phoneRegex];
BOOL matches = [test evaluateWithObject:phoneNumber];

Answer 4

Below code will work for your requirement:
Function:
-(BOOL)validatePhone:(NSString *)enteredPhoneNumber
{
NSString *phoneRegex = #"[789][0-9]{9}";
// OR below for advanced type
//NSString *phoneRegex = #"^((\\+)|(00))[0-9]{6,14}$";
NSPredicate *phoneTest = [NSPredicate predicateWithFormat:#"SELF MATCHES %#", phoneRegex];
return [phoneTest evaluateWithObject:enteredPhoneNumber];
}
Call it:
if ([self validatePhone:#"9833112299"])
{
NSLog(#"Valid Phone Number");
}
else
{
NSLog(#"Invalid Phone Number");
}

Answer 5

Make it Global using 'extension' use it wherever required
In any one of your view controller class at the end after last } paste below code
extension String
{
func validateMobile() -> Bool
{
return NSPredicate(format: "SELF MATCHES %#","[789][0-9].{9}").evaluate(with: self)
}
}
when you want to validate yourTxtField in any ViewController class simply call as below:
if (yourTxtField.text?.validateMobile())!
{
print("It is 10 digit, starting with 7/8/9")
}
else
{
print("Invalid mobile number")
}