Hi i have created a code to validate my script but i cant figure out how to make the hphone and fax numeric and "10" digits any suggestions pls
HTML Code:
function validate_form ()
{
	valid = true;

        if ( document.input.name.value == "" )
        {
                alert ( "Please enter your name" );
                valid = false;
        }
				
				if ( document.input.address.value == "" )
        {
                alert ( "Please enter your address address" );
                valid = false;
        }
		
				if ( document.input.town.value == "" )
        {
                alert ( "Please enter your Suburb or town" );
                valid = false;
        }
  				if ( document.input.postcode.value == "" )
        {
                alert ( "Please enter your postocde" );
                valid = false;
        }
				
				if ( document.input.hphone.value == "" )
        {
                alert ( "Please enter your home phone number" );
                valid = false;				
		}		
				if ( document.input.wphone.value == "" )
        {
                alert ( "Please enter your work phone number" );
                valid = false;
        }
        		if ( document.input.fax.value == "" )
        {
                alert ( "Please enter your fax" );
                valid = false;
        }
        
        	if ( document.input.daydropdown.value == "" )
        {
                alert ( "Please enter day for delivery" );
                valid = false;
        }
		
				if ( document.input.monthdropdown.value == "" )
        {
                alert ( "Please enter month for delivery" );
                valid = false;
        }
        		if ( document.input.yeardropdown.value == "" )
        {
                alert ( "Please enter year of delivery" );
                valid = false;
        }
        {
 var x=document.forms["input"]["email"].value;
 var atpos=x.indexOf("@");
 var dotpos=x.lastIndexOf(".");
 if (atpos<1 || dotpos<atpos+2 || dotpos+2>=x.length)
   {
   alert("Not a valid e-mail address");
   return false;
   }
	}
        return valid;
}
function setVisible(id, visible) {
        var o = document.getElementById(id);
        if (typeof(o) != 'undefined') o.style.visibility = visible ? 'visible' : 'hidden';
        if (typeof(o) == 'undefined') alert("Element with id '" + id + "' not found.");
    }

    function setDisplay(id, visible) {
        var o = document.getElementById(id);
        if (typeof(o) != 'undefined') o.style.display = visible ? 'block' : 'none';
        if (typeof(o) == 'undefined') alert("Element with id '" + id + "' not found.");
    }