function CheckBoxValidatorEvaluateIsValid(val)
{
    var control = document.getElementById(val.controltovalidate);
    var mustBeChecked = Boolean(val.mustBeChecked);

    return control.checked == mustBeChecked;
}

function CheckBoxListValidatorEvaluateIsValid(val)
{
    var control = document.getElementById(val.controltovalidate);
    var minimumNumberOfSelectedCheckBoxes = 1//parseInt(val.minimumNumberOfSelectedCheckBoxes);

    var selectedItemCount = 0;
    var liIndex = 0;
    var currentListItem = document.getElementById(control.id + '_' + liIndex.toString());
    while (currentListItem != null)
    {
        if (currentListItem.checked) selectedItemCount++;
        liIndex++;
        currentListItem = document.getElementById(control.id + '_' + liIndex.toString());
    }
    
    return selectedItemCount >= minimumNumberOfSelectedCheckBoxes;
}


function CheckBoxListValidatorEvaluateIsValidClientValidate(source, clientside_arguments) {

    var val = source;
    var control = document.getElementById(val.attributes("CheckBoxListToValidate").value);
    var minimumNumberOfSelectedCheckBoxes = 1//parseInt(val.minimumNumberOfSelectedCheckBoxes);

    var selectedItemCount = 0;
    var liIndex = 0;
    var currentListItem = document.getElementById(control.id + '_' + liIndex.toString());
    while (currentListItem != null) {
        if (currentListItem.checked) selectedItemCount++;
        liIndex++;
        currentListItem = document.getElementById(control.id + '_' + liIndex.toString());
    }

    if (selectedItemCount >= minimumNumberOfSelectedCheckBoxes)
    {
        clientside_arguments.IsValid = true;
    }
    else { 
    clientside_arguments.IsValid = false };
}