// JavaScript Document

	// return true if the typed char is allowed
	function keyRestrict(event, validCharsRegexp)
	{
		var char = event.which;
		alert(char +' = ' + String.fromCharCode(event.which));
		return  validCharsRegexp && String.fromCharCode(event.which).match(event.charCode, validCharsRegexp);
	}

	function keyRestrictToNumbers(event)
	{
		alert(keyRestrict(event, '/[0-9]/'));
		// Allow only backspace, delete, tab, numeric, numpad numeric, arrows
			if ( event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || (event.keyCode >= 48 && event.keyCode <= 57) || (event.keyCode >= 96 && event.keyCode <= 105) || (event.keyCode >= 37 && event.keyCode <= 40) ) {
				// let it happen, don't do anything
			}
			else 
			{
				event.preventDefault();   
			}
	}
	
	
	function keyRestrictToDate(event)
	{
		// Allow only backspace, delete, tab, numeric, numpad numeric, arrows and the date delimitator '/'
			if ( event.keyCode == 46 || event.keyCode == 8 || event.keyCode == 9 || (event.keyCode >= 48 && event.keyCode <= 57) || (event.keyCode >= 96 && event.keyCode <= 105) || (event.keyCode >= 37 && event.keyCode <= 40) || event.keyCode == 191) {
				// let it happen, don't do anything
			}
			else 
			{
				event.preventDefault();   
			}
	}