GridView渲染后做的展开折叠效果

  $(document).ready(function() {
             $("#dgvCategoryList").find("tr").slice(1).each(function(i) {
                 var cateId = $(this).attr("cateId");
                 var parentCateId = $(this).attr("parentCateId");
                 if (parentCateId.length == 0) {
                     var img = "<img src='../Content/Images/menu_plus.gif' onclick='toggleChildrenRow(this)' style='cursor:hand'></img>";
                     var cateNameDom = $($(this).find("td:first")[0]).children(":first")[0];
                     $(img).insertBefore($(cateNameDom));
                 }
                 else {
                     $(this).css("display","none");
                 }
             });
         });
         function toggleChildrenRow(imgDom) {
             var currentRow = $(imgDom).parent().parent();
             var cateId = currentRow.attr("cateId");
             var imgSrc = $(imgDom).attr("src");
             var visibly;
             if (imgSrc.indexOf("menu_plus.gif") > 0) {
                 visibly = true;
                 $(imgDom).attr("src", "../Content/Images/menu_minus.gif");
             }
             else {
                 visibly = false;
                 $(imgDom).attr("src", "../Content/Images/menu_plus.gif");
             }
             $("#dgvCategoryList").find("tr[parentCateId='" + cateId + "']").each(function(i) {
                 if (visibly == true) {
                     $(this).show("fast");
                 }
                 else {
                     $(this).hide("fast");
                 }
             });
         }