allow only to enter english characters in iPhone UITextField

I want to allow user to enter only english alphabets and characters. How can i prevent user from entering other charact开发者_如何学Pythoners than english.

Check out UIKeyboardType - there is an option to support only ASCII (UIKeyboardTypeASCIICapable).

Also, there are options in the UITextFieldDelegate protocol that could allow you to selectively filter input. Take a look at:

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