keyBoard of textfield in iPhone- using alphanumeric chararacter

I am new to iPhone technology and I want to use TextField, but when I use keyboard I can't use alphanumeric character. It's working only for alphabetic words.

Some functions I have used are below:-

-(BOOL)textFieldShouldReturn:(UITextField *)theTextField {

  if(theTextField == txtanswer) {
    [txtanswer resignFirstResponder];
  }
  return YES;
}



- (void)textFieldDidBeginEditing:(UITextField *)textField
{
    CGRect textFieldRect =
  //[self.view.window convertRect:textField.bounds fromView:textField];
    CGRect viewRect =
  //[self.view.window convertRect:self.view.bounds fromView:self.view];
  CGFloat midline = textFieldRect.origin.y + 0.5 * textFieldRect.size.height;
    CGFloat numerator =
  midline - viewRect.origin.y
  - MINIMUM_SCROLL_FRACTION * viewRect.size.height;
    CGFloat denominator =
  (MAXIMUM_SCROLL_FRACTION - MINIMUM_SCROLL_FRACTION)
  * viewRect.size.height;
    CGFloat heightFraction = numerator / denominator;
  if (heightFraction < 0.0)
    {
        heightFraction = 0.0;
    }
    else if (heightFraction > 1.0)
    {
        heightFraction = 1.0;
    }

  UIInterfaceOrientation orientation =
  [[UIApplication sharedApplication] statusBarOrientation];
    if (orientation == UIInterfaceOrientationPortrait ||
        orientation == UIInterfaceOrientationPortraitUpsideDown)
    {
        animatedDistance = floor(PORTRAIT_KEYBOARD_HEIGHT * heigh开发者_运维百科tFraction);
    }
    else
    {
        animatedDistance = floor(LANDSCAPE_KEYBOARD_HEIGHT * heightFraction);
    }

  CGRect viewFrame = self.view.frame;
    viewFrame.origin.y -= animatedDistance;

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

    [self.view setFrame:viewFrame];

    [UIView commitAnimations];
}

- (BOOL)textFieldShouldBeginEditing:(UITextField *)textField
{
  if(cehc==2)
  {


  }if(textField == txtanswer) 

    [txtanswer resignFirstResponder];
  return YES;
}
-(IBAction) textFieldDoneEditing : (id) sender{
    CGRect viewFrame = self.view.frame;
    viewFrame.origin.y += animatedDistance;

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

    [self.view setFrame:viewFrame];

    [UIView commitAnimations];
}

- (void)textFieldDidEndEditing:(UITextField *)textField;
{
    CGRect viewFrame = self.view.frame;
    viewFrame.origin.y += animatedDistance;

    [UIView beginAnimations:nil context:NULL];
    [UIView setAnimationBeginsFromCurrentState:YES];
    [UIView setAnimationDuration:KEYBOARD_ANIMATION_DURATION];

    [self.view setFrame:viewFrame];

    [UIView commitAnimations];
}

Please help me out to solve this problem

Thanks Kunal

Does UIKeyboardType in the XCode docs help you (or did I misunderstand your problem)? Note that there seems to be 3 different numeric keyboard types.