That proposed solution was so lame. It still prevents the drop operation from occuring. I've found my solution with the following JQuery code which will allow multiple-row drag/drop operations until I am ready to post the data back to the server:
<script type="text/javascript">
//... Control key and mouse click toggles row selection.
$("#<%= GridView1.ClientID %> tbody").on('click', 'tr', function (e) {
if (e.ctrlKey || e.metaKey) {
$(this).toggleClass("selected");
} else {
$(this).addClass("selected").siblings().removeClass('selected');
}
}).sortable({
axis: 'y', //... Just row movement.
connectWith: "#<%= GridView1.ClientID %> tbody",
containment: 'parent', //... Drag only within parent.
cursor: 'move', //...Move cursor.
delay: 150, //... Needed to prevent accidental drag when trying to select.
items: 'tr:not(Spud)', //... Not spud rows.
revert: 0,
helper: function (e, item) {
var helper = $('<tr/>');
if (!item.hasClass('selected')) {
item.addClass('selected').siblings().removeClass('selected');
}
var elements = item.parent().children('.selected').clone();
item.data('multidrag', elements).siblings('.selected').remove();
return helper.append(elements);
},
stop: function (e, info) {
info.item.after(info.item.data('multidrag')).remove();
$('.selected').each(function () {
alert($(this).find('.Rig').val());
});
}
});
</script>