js中获取宽高

<script type="text/javascript">
    function getWH() {
        var a = "";
        a += " 网页可见区域宽：" + document.body.clientWidth + "\n";
        a += " 网页可见区域高：" + document.body.clientHeight + "\n";
        a += " 网页可见区域宽：" + document.body.offsetWidth + " (包括边线和滚动条的宽)" + "\n";
        a += " 网页可见区域高：" + document.body.offsetHeight + " (包括边线的宽)" + "\n";
        a += " 网页正文全文宽：" + document.body.scrollWidth + "\n";
        a += " 网页正文全文高：" + document.body.scrollHeight + "\n";
        a += " 网页被卷去的高(ff)：" + document.body.scrollTop + "\n";
        a += " 网页被卷去的高(ie)：" + document.documentElement.scrollTop + "\n";
        a += " 网页被卷去的左：" + document.body.scrollLeft + "\n";
        a += " 网页正文部分上：" + window.screenTop + "\n";
        a += " 网页正文部分左：" + window.screenLeft + "\n";
        a += " 屏幕分辨率的高：" + window.screen.height + "\n";
        a += " 屏幕分辨率的宽：" + window.screen.width + "\n";
        a += " 屏幕可用工作区高度：" + window.screen.availHeight + "\n";
        a += " 屏幕可用工作区宽度：" + window.screen.availWidth + "\n";
        a += " 你的屏幕设置是 " + window.screen.colorDepth + " 位彩色" + "\n";
        a += " 你的屏幕设置 " + window.screen.deviceXDPI + " 像素/英寸" + "\n";
        alert(a);
    }
</script>