//Used to check that only numbers are entered     
function checkNumber(source, args)
{
    var text = args.Value;
    
    for(var i = 0; i < text.length; i++)
    {
        var character = text.charAt(i);
        
        if(character.match("([0-9])"))
        {
            //do nothing
        }
        else
        {
            args.IsValid = false;
            return;
        }                
    } 
    
    args.IsValid = true;
}