各位大大您好，請問如何使用javascript來新增移除asp:imagebutton的imageurl，目前能在
$('.ib').attr('src', '');
可以成功移除asp:imagebutton的圖片，但是無法新增回來，請問如何新增imagebutton的圖片，javascript如下：

<script>
$(document).ready(function () {
//如果瀏覽器放大縮小時
            $(window).resize(function () {
            if (window.matchMedia('only screen and (max-width: 1000px)').matches) {
//移除圖片
                $('.ib').attr('src', '');
            }
            else  {
//加入圖片
//無法成功
                $('#ImageButton1').attr('src', 'MasterImages\BtLink01.png');
                $('#ImageButton2').attr('src', 'MasterImages\BtLink02.png');
                $('#ImageButton3').attr('src', 'MasterImages\BtLink03.png');
                $('#ImageButton4').attr('src', 'MasterImages\BtLink04.png');
                $('#ImageButton5').attr('src', 'MasterImages\BtLink05.png');
                $('#ImageButton6').attr('src', 'MasterImages\BtLink06.png');
            }})
//第一次開啟網站時
            if(<%=(Not Page.isPostBack).ToString().ToLower() %>) chkMedia();  
});
        function chkMedia(){
            if (window.matchMedia('only screen and (max-width: 1000px)').matches) {
//移除圖片
                $('.ib').attr('src', '');
            }
            else {
//加入圖片
//無法成功
                $('#ImageButton1').attr('src', 'MasterImages\BtLink01.png');
                $('#ImageButton2').attr('src', 'MasterImages\BtLink02.png');
                $('#ImageButton3').attr('src', 'MasterImages\BtLink03.png');
                $('#ImageButton4').attr('src', 'MasterImages\BtLink04.png');
                $('#ImageButton5').attr('src', 'MasterImages\BtLink05.png');
                $('#ImageButton6').attr('src', 'MasterImages\BtLink06.png');
 };        };
</script>

body如下：

</ul>
//imagebutton
<div id="LinkWebBt">
<asp:ImageButton class="ib" ID="ImageButton1" AlternateText="xxoo" runat="server" ImageUrl="MasterImages\BtLink01.png" PostBackUrl="http://www.taipei.gov.tw"></asp:ImageButton>
 <asp:ImageButton class="ib" ID="ImageButton2" AlternateText="xxoo" runat="server" ImageUrl="MasterImages\BtLink02.png" PostBackUrl="http://www.cpami.gov.tw/chinese"></asp:ImageButton>
<asp:ImageButton class="ib" ID="ImageButton3" AlternateText="xxoo" runat="server" ImageUrl="MasterImages\BtLink03.png" PostBackUrl="http://www.pwb.taipei.gov.tw"></asp:ImageButton>
<asp:ImageButton class="ib" ID="ImageButton4" AlternateText="xxoo" runat="server" ImageUrl="MasterImages\BtLink04.png" PostBackUrl="http://web3.moeaboe.gov.tw"></asp:ImageButton>
<asp:ImageButton class="ib" ID="ImageButton5" AlternateText="xxoo" runat="server" ImageUrl="MasterImages\BtLink05.png" PostBackUrl="http://www.nco.taipei.gov.tw"></asp:ImageButton>
<asp:ImageButton class="ib" ID="ImageButton6" AlternateText="xxoo" runat="server" ImageUrl="MasterImages\BtLink06.png" PostBackUrl="http://www.pcc.gov.tw"></asp:ImageButton>
</div>

謝謝各位大大!