<script language="javascript">
    function ChangeChk(ctl)
    {
      var theBox=ctl;
          var elem=theBox.form.elements;
          for(i=0;i<elem.length;i++)
          {
        if(elem[i].type=='radio')
        {
               if(elem[i].id==theBox.id)
               {
                  elem[i].checked=true;
               }
               else
               {
          elem[i].checked=false;
               }
               }
               }
        }
        </script>

...
Datalist模板列
<ItemTemplate>
<asp:RadioButton id="Chk" Runat="server" Width="60px" onclick="ChangeChk(this)"></asp:RadioButton>
</ItemTemplate>
..