function checkRequiredFields(input)
{

    var website = document.getElementById("website").value;

    if (website != "") {
         return false;
    }


    var amount_check = document.getElementById("amount").value;
    var amount_num = parseInt(amount_check.charAt(0));

     if ((amount_num == NaN) || (amount_num == 0)) {
alert ("Your pledge amount is zero.");
         return false;
}

 

    var requiredFields = new Array("name",
                                   "address",
                                   "email",
								   "zip");
    var fieldNames = new Array("Name",
                               "Address",
                               "Email",
							   "Zipcode");

    var fieldCheck   = true;
    var fieldsNeeded = "\nA value must be entered in the following field(s):\n\n\t";

    for(var fieldNum=0; fieldNum < requiredFields.length; fieldNum++) {
        if ((input.elements[requiredFields[fieldNum]].value == "") ||
            (input.elements[requiredFields[fieldNum]].value == " ")) {

            fieldsNeeded += fieldNames[fieldNum] + "\n\t";
            fieldCheck = false;
        }
    }

    if (fieldCheck == true)
    {
        return true;
    }
    else
    {
        alert(fieldsNeeded);
        return false;
    }
}
function toAlpha(checkString)
{
    newString = "";    
    count = 0;         

    for (i = 0; i < checkString.length; i++) {
        ch = checkString.substring(i, i+1);
        if ((ch >= "a" && ch <= "z") || (ch >= "A" && ch <= "Z" )) {
            newString += ch;
        }
    }

    return newString;
}