Email validation in UITextField

Create a function for validating email like the code below :

- (BOOL)validateEmail:(NSString *)emailStr 

{

  NSString *emailRegex = @"[A-Z0-9a-z._%+-]+@[A-Za-z0-9.-]+\\.[A-Za-z]{2,4}";

   NSPredicate *emailTest = [NSPredicate predicateWithFormat:@"SELF MATCHES %@", emailRegex];

    return [emailTest evaluateWithObject:emailStr];

}

UITextField delegate has a method textFieldDidEndEditing, write the code below to display an alert message when email is not valid :

if (textField == email)

    {

        

if(![self validateEmail:[email text]])

        {

            // user entered invalid email address

  UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"Error" message:@"Enter a valid email address." delegate:self cancelButtonTitle:nil otherButtonTitles:@"OK", nil];

            [alert show];

           

            //email.text=@"";

        }

    }