iOS TextField Validation

Question

I need a way to ensure that phone numbers have 10 digits with no other characters ie () - and make sure that email addresses are valid emails (formatted correctly).

Is t

Answer 1

Here's a simple way of ensuring phonenumber length in the UIViewController that has the text field in it's view.

- (void)valueChanged:(id)sender
{
    if ([[[self phoneNumberField] text] length] > 10) {
        [[self phoneNumberField] setText:[[[self phoneNumberField] text] 
          substringToIndex:10]]; 
    } 
}

- (void) viewWillAppear:(BOOL)animated
{
    [[self phoneNumberField] addTarget:self 
                            action:@selector(valueChanged:) 
                            forControlEvents:UIControlEventEditingChanged];
}

For emails I suppose you want to check against a regexp when it loses focus.