function set_formValidadeFieldStyle(source, isValid)
{
    document.getElementById(source.controltovalidate).className = (isValid) ? "" : "requiredField";
}

function formValidateTextBox(source, args)
{
    args.IsValid = args.Value != "";
    set_formValidadeFieldStyle(source, args.IsValid);
}

function formValidateDropDownListZeroIndex(source, args)
{
    args.IsValid = args.Value >= 0;
    set_formValidadeFieldStyle(source, args.IsValid);
}

function formValidateDropDownList(source, args)
{
    args.IsValid = args.Value > 0;
    set_formValidadeFieldStyle(source, args.IsValid);
}