iOS限制输入框输入多个标点符号以及小数点保留后两位

iOS限制输入框输入多个标点符号以及小数点保留后两位

#pragma mark - UITextField Delegate 
- (BOOL)textField:(UITextField *)textField shouldChangeCharactersInRange:(NSRange)range replacementString:(NSString *)string {
    // 判断是否已经存在小数点
    if ([string isEqualToString:@"."] && [textField.text stringByReplacingOccurrencesOfString:@" " withString:@""].length == 0) {
        textField.text = @"";
        return NO;
    } else if ([string isEqualToString:@"."] && [textField.text containsString:@"."]) {
        return NO;
    }

    NSMutableString * futureString = [NSMutableString stringWithString:textField.text];
    [futureString  insertString:string atIndex:range.location];
    NSInteger flag=0;
    const NSInteger limited = 2;  // 小数点  限制输入两位
    for (NSInteger i = futureString.length-1; i>=0; i--) {
        if ([futureString characterAtIndex:i] == '.') {
            if (flag > limited)   return NO;
            break;
        }
        flag++;
    }
    return YES;
}