Question

I have some text fields on my project.

I want that input types of text fields are only one type. For example credit card number text field’s input must be only decimals and user enter another type character, it will remove or not accept in the text field.

Sorry my bad english.

Answer 1

you can declare like the below and use

#define LEGAL   @"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz "


// allow only legal letters
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string
{
    NSCharacterSet *cs = [[NSCharacterSet characterSetWithCharactersInString:LEGAL] invertedSet];
    NSString *filtered = [[string componentsSeparatedByCharactersInSet:cs] componentsJoinedByString:@""];
    return [string isEqualToString:filtered];
}

and we can use like this also

entryField.keyboardType = UIKeyboardTypeNumbersAndPunctuation;