JavaScript实现在文本框中输入空格时自动填写某个值

  <script language="javascript" type="text/javascript">
      var txtText4 = "#" + '<%= new DynamicControl(this, "Text4").ClientID%>';

      $(function () {
                 $(txtText4).keyup(function (e) {
              if (e.which == 32)
                  $(this).val("TEXT");
          });
      });

   </script>