前台调用的高级js弹出窗口实例

<script type="text/javascript">
       var docEle = function() {
           return document.getElementById(arguments[0]) || false;
       }

       function openNewDiv(_id) {
           var m = "mask";
           if (docEle(_id)) document.body.removeChild(docEle(_id));
           if (docEle(m)) document.body.removeChild(docEle(m));

           //mask遮罩层

           var newMask = document.createElement("div");
           newMask.id = m;
           newMask.style.position = "absolute";
           newMask.style.zIndex = "1";
           _scrollWidth = Math.max(document.body.scrollWidth, document.documentElement.scrollWidth);
           _scrollHeight = Math.max(document.body.scrollHeight, document.documentElement.scrollHeight);
           newMask.style.width = _scrollWidth + "px";
           newMask.style.height = _scrollHeight + "px";
           newMask.style.top = "0px";
           newMask.style.left = "0px";
           newMask.style.background = "#33393C";
           newMask.style.filter = "alpha(opacity=40)";
           newMask.style.opacity = "0.40";
           document.body.appendChild(newMask);

           //新弹出层

           var newDiv = document.createElement("div");