function Check_Num(tocheck)
{
	var isnum = true;
	
	if (tocheck == null || tocheck == "")
	{
		isnum = false;
		return isnum;
	}
	
	for (var j = 0 ; j < tocheck.length; j++)
	{
		if (      tocheck.substring(j, j + 1) != "0"
			&&   tocheck.substring(j, j + 1) != "1"
			&&   tocheck.substring(j, j + 1) != "2"
			&&   tocheck.substring(j, j + 1) != "3"
			&&   tocheck.substring(j, j + 1) != "4"
			&&   tocheck.substring(j, j + 1) != "5"
			&&   tocheck.substring(j, j + 1) != "6"
			&&   tocheck.substring(j, j + 1) != "7"
			&&   tocheck.substring(j, j + 1) != "8"
			&&   tocheck.substring(j, j + 1) != "9" )
		{
			isnum = false;
		}
	}
	return isnum;
}