银行卡输入自动断开 如1111 2222 3333 444

代理就不用多说了

- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string{            NSString *text = [textField text];                        NSCharacterSet *characterSet =            [NSCharacterSet characterSetWithCharactersInString:@"0123456789\n"];            string = [string stringByReplacingOccurrencesOfString:@" " withString:@""];            if ([string rangeOfCharacterFromSet:[characterSet invertedSet]].location !=                NSNotFound) {                return NO;            }                        text = [text stringByReplacingCharactersInRange:range withString:string];            text = [text stringByReplacingOccurrencesOfString:@" " withString:@""];                        NSString *newString = @"";            while (text.length > 0) {                NSString *subString = [text substringToIndex:MIN(text.length, 4)];                newString = [newString stringByAppendingString:subString];                if (subString.length == 4) {                    newString = [newString stringByAppendingString:@" "];                }                text = [text substringFromIndex:MIN(text.length, 4)];            }                        newString =            [newString stringByTrimmingCharactersInSet:[characterSet invertedSet]];                        if (newString.length >= 24) {                return NO;            }                        [textField setText:newString];                        return NO;}

1111 2222 3333 444