// 页面尚未加载时的loading图

            var _PageHeight = document.documentElement.clientHeight,

                 _PageWidth = document.documentElement.clientWidth;

             var _LoadingTop = _PageHeight > 61 ? (_PageHeight - 61) / 2 : 0,

                 _LoadingLeft = _PageWidth > 215 ? (_PageWidth - 215) / 2 : 0;

             var _LoadingHtml = '<div id="loadingDiv" class="loadingDiv" style="position:absolute;left:0;width:100%;height:' + _PageHeight + 'px;top:0;background:#000;opacity:1;filter:alpha(opacity=80);z-index:10000;">'+

                                    '<div style="position: absolute; cursor: wait; left: ' + _LoadingLeft + 'px; top:' + _LoadingTop + 'px; width:auto;padding:0 8px;background: #fff; font-size: 14px;" ><img style="width:50px;height:50px;display: inlin-block;" src="./style/img/load.gif"><span>页面加载中，请稍候...</span></div>'+

                                '</div>';

             document.write(_LoadingHtml);

             document.onreadystatechange = completeLoading;

             function completeLoading() {

                 if (document.readyState == "complete") {

                    //  debugger

                     var loadingMask = document.getElementById('loadingDiv');

                     loadingMask.parentNode.removeChild(loadingMask);

                 }

             }