关于JS 的一个小问题.请赐教

HTML代码如下:

 <div id="sj">
    <a href="#"><img src="#"  newsrc="#"  >12</a>
    <a href="#"><img src="#" newsrc="#" >2</a>
    <a href="#"><img src="#" newsrc="#" >3</a>
    <a href="#"><img src="#" newsrc="#" >4</a>
</div>

js代码如下:

 window.onload=function() {
            var oSh = document.getElementById('sj');
            var oimg = oSh.getElementsByTagName('img');

            for (var i = 0; i < oimg.length; i++) {

                oimg[i].onclick=function()
                {
                 this.src=
                };
        };

            写到这里就卡住了.我不知道怎么让当前的src替换成和他对应的newsrc;
            请大神给力啊.

    window.onload = function () {
        var oSh = document.getElementById('sj');
        var oimg = oSh.getElementsByTagName('img');
        for (var i = 0; i < oimg.length; i++) {

            oimg[i].onclick = function () {
                this.src = this.getAttribute('newsrc')///////////
            };
        }
    }

$(this).attr("src", $(this).attr("newsrc"));