allow only to enter english characters in iPhone UITextField

问题

I want to allow user to enter only english alphabets and characters. How can i prevent user from entering other characters than english.

回答1:

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;

来源：https://stackoverflow.com/questions/2475405/allow-only-to-enter-english-characters-in-iphone-uitextfield