function checkAll(count) {
    for (i = 0; i < count.value; i++) {
       var z = "files["+i+"]";
       box = document.dl_form.elements[z];
       box.checked = true;
    }
}

function uncheckAll(count) {
    for (i = 0; i < count.value; i++) {
       var z = "files["+i+"]";
       box = document.dl_form.elements[z];
       box.checked = false;
    }
}


function alf(count) {
    for (i = 0; i < count.value; i++) {
       var z = "files["+i+"]";
       box = document.dl_form.elements[z];
       if (box.checked) return true;
    }
alert("Please select at least one document!");
return false;
}