，为什么不上你的下拉使用jQuery的onChange事件？

Instead of using a form, why not use a jQuery onChange event on your drop down?

$(document).ready(function() {
    $("#ddl").change(function() {
        var strSelected = "";
        $("#ddl option:selected").each(function() {
            strSelected += $(this)[0].value;
        });
        var url = "/Home/MyAction/" + strSelected;

        $.post(url, function(data) {
            // do something if necessary
        });
    });
});