js判断客户端浏览器版本[仅限IE]

<script language="javascript">
function getIEVersion()
{
    if(navigator.appName == "Microsoft Internet Explorer")
    {
           if(navigator.appVersion.match(/7./i)=='7.')
           {
                  alert( '当前浏览器是IE 7' )
           }
           if(navigator.appVersion.match(/6./i)=='6.')
           {
                  alert( '当前浏览器是IE 6' )
           }
           ..........................................................
           ..........................................................
    }
}
</script>

<input type="button" name="getIEVersion" value="获取当前浏览器版本" onclick="getIEVersion();" />