function clrTxt(controlid, textDefault) {
    if (document.getElementById(controlid).value == textDefault) {
        document.getElementById(controlid).value = "";
    }
}

function LUNCheck(src, arg) {

    number = arg.Value;

    var i, sum, weight;
    sum = 0;
    for (i = 0; i < number.length - 1; i++) {
        weight = number.substr(number.length - (i + 2), 1) * (2 - (i % 2));
        sum += ((weight < 10) ? weight : (weight - 9));
    }

    if (parseInt(number.substr(number.length - 1)) == ((10 - sum % 10) % 10)) {
        arg.IsValid = true;

    } else {

        //alert("Invalid card number");

        arg.IsValid = false;
    }

}

function cambiaImmagineXXXXXXXXXXXXXXXXXXXXXXXX(iddiv, linkimg) {
    if (document.getElementById) {
        document.getElementById(iddiv).style.background = "url(" + linkimg + ") no-repeat";
    }
}

function cambiaImmagine(iddiv, linkimg, idthumb, numeroImg) {
    if (document.getElementById) {
        document.getElementById(iddiv).style.background = "url(" + linkimg + ")";
        for (i = 0; i <= numeroImg; i++) {
            var currentImg;
            currentImg = "thumbimg_" + i;
            if (currentImg == idthumb) {
                if (document.getElementById(currentImg).style.MozOpacity) document.getElementById(currentImg).style.MozOpacity = 1.0;
                if (document.getElementById(currentImg).style.opacity) document.getElementById(currentImg).style.opacity = 1.0;
                if (document.all) document.getElementById(currentImg).filters.alpha.opacity = 100;
            }
            else {
                if (document.getElementById(currentImg).style.MozOpacity) document.getElementById(currentImg).style.MozOpacity = 0.6;
                if (document.getElementById(currentImg).style.opacity) document.getElementById(currentImg).style.opacity = 0.6;
                if (document.all) document.getElementById(currentImg).filters.alpha.opacity = 60;
            }

        }
    }
}