function _(id) {
    return document.getElementById(id)
}

function addSortToForm(sourceElement) {
    var myField = document.createElement("input")
    myField.type = "hidden"
    myField.value = sourceElement.value
    myField.name = sourceElement.name
    myField.id = "hidden_"+sourceElement.name

    var form = _('sort_save_form')
    var elem = _(myField.id)
    if (elem) {
        elem.value = myField.value
    } else {
        form.appendChild(myField)
    }
}