get all internet explroer versions

ieversnippet.js

function getInternetExplorerVersion()
    // Returns the version of Internet Explorer or a -1
    // (indicating the use of another browser).
    // see https://msdn.microsoft.com/en-us/library/ms537509(v=vs.85).aspx
    // but for ie 11 doenst work this way
    
{
    var rv = -1; // Return value assumes failure.
    if (navigator.appName == 'Microsoft Internet Explorer') {
        var ua = navigator.userAgent;
        var re = new RegExp("MSIE ([0-9]{1,}[\.0-9]{0,})");
        if (re.exec(ua) != null)
            rv = parseFloat(RegExp.$1);
    } else   if (navigator.appName == 'Netscape') {
            var ua = navigator.userAgent;
            var re = new RegExp("Trident/.*rv:([0-9]{1,}[\.0-9]{0,})");
            if (re.exec(ua) != null)
                rv = parseFloat(RegExp.$1);
    }
    return rv;
}