第二种方式AJAX调用。

The second way ajax call.

<script language="javascript" type="text/javascript">
  $(document).ready(function () {
      // storing selected value to hidden field
      $("#Selected").val($("#id").val()); 

      $("#id").change(function () { 
        $.ajax({
           url: "~/ ControllerName/ActionMethodName",
           type: 'POST',
           cache: false,
           data: { Selected: $("# Selected").val() },
           success: function (data) {
             //
           }
         });
  });
  )};
</script>

控制器：

private string ActionMethodName (string Selected)
{
  String value = Selected; 
}