Html:
<table id="Table5" class="querytable" width="100%">
     <tr>
         <th>
             <input name="chkall" value="1" style="width:25px; text-align:center;" type="checkbox" onclick="CheckAll(this,'Item')"/>全选 
           </th>
          <th>
             销售部门
           </th>
          <th>
              销售单号
            </th>
          <th>
              是否导出开票文本
            </th>
          <th>
              是否导入A6
          </th>
      </tr>
<asp:Repeater ID="rptUjlist" runat="server" >
<ItemTemplate>
    <tr onmouseover="c=this.style.backgroundColor;this.style.backgroundColor='#C2DFF7'"
onmouseout="this.style.backgroundColor=c;">                                   <td>
            <input name="Item" style="width:20px; text-align:center" type="checkbox" value='<%# Eval("ID") %>' />
        </td>
        <td id="Td1" runat="server">
             <%# Eval("Tcbm")%>
        </td>
        <td>
             <%# Eval("xsdh")%>
        </td>
        <td>
           <%# Eval("sfdckp")%>
        </td>
        <td>
            <%# Eval("sfdrA6")%>
            <asp:HiddenField ID="hFNo" runat="server" Value=' <%# Eval("xsdh")%>' />
        </td>
     </tr>
</ItemTemplate>
</asp:Repeater>
</table>
JS代码
function CheckAll(e, itemname) {
    var aa = document.getElementsByName(itemname);
    if (aa == undefined) return;
    for (var i = 0; i < aa.length; i++) aa[i].checked = e.checked;
}
后台代码
string str = Request.Form["Item"]
str就是获取的<%# Eval("ID") %>中绑定的值