I'm no ASP expert, but I can tell you that OnServerClick isn't a client-side event. It's server side, so of course the form has to get sent to the server for the server to see it. If you want ...
$.ajax({ data: criteria, datatype: "application/json", type: "POST", url: "MI/DeleteItem/" + ItemID, cache: false, success: function (result) {... You've seen these ...
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