funções javascript

[fil79]

tenho visto que muitos sites que usam flash usam as seguintes funções javascript:

//v1.7
// Flash Player Version Detection
// Detect Client Browser type
// Copyright 2005-2007 Adobe Systems Incorporated.  All rights reserved.
var isIE  = (navigator.appVersion.indexOf("MSIE") != -1) ? true : false;
var isWin = (navigator.appVersion.toLowerCase().indexOf("win") != -1) ? true : false;
var isOpera = (navigator.userAgent.indexOf("Opera") != -1) ? true : false;

function ControlVersion()
{
    var version;
    var axo;
    var e;

    // NOTE : new ActiveXObject(strFoo) throws an exception if strFoo isn't in the registry

    try {
        // version will be set for 7.X or greater players
        axo = new ActiveXObject("ShockwaveFlash.ShockwaveFlash.7");
        version = axo.GetVariable("$version");
    } catch (e) {
    }

    if (!version)
    {
        try {
            // version will be set for 6.X players only
            axo = new ActiveXObject("ShockwaveFlash.ShockwaveFlash.6");
            
            // installed player is some revision of 6.0
            // GetVariable("$version") crashes for versions 6.0.22 through 6.0.29,
            // so we have to be careful.
            
            // default to the first public version
            version = "WIN 6,0,21,0";

            // throws if AllowScripAccess does not exist (introduced in 6.0r47)        
            axo.AllowScriptAccess = "always";

            // safe to call for 6.0r47 or greater
            version = axo.GetVariable("$version");

        } catch (e) {
        }
    }

    if (!version)
    {
        try {
            // version will be set for 4.X or 5.X player
            axo = new ActiveXObject("ShockwaveFlash.ShockwaveFlash.3");
            version = axo.GetVariable("$version");
        } catch (e) {
        }
    }

    if (!version)
    {
        try {
            // version will be set for 3.X player
            axo = new ActiveXObject("ShockwaveFlash.ShockwaveFlash.3");
            version = "WIN 3,0,18,0";
        } catch (e) {
        }
    }

    if (!version)
    {
        try {
            // version will be set for 2.X player
            axo = new ActiveXObject("ShockwaveFlash.ShockwaveFlash");
            version = "WIN 2,0,0,11";
        } catch (e) {
            version = -1;
        }
    }
   
    return version;
}

// JavaScript helper required to detect Flash Player PlugIn version information
function GetSwfVer(){
    // NS/Opera version >= 3 check for Flash plugin in plugin array
    var flashVer = -1;
   
    if (navigator.plugins != null && navigator.plugins.length > 0) {
        if (navigator.plugins["Shockwave Flash 2.0"] || navigator.plugins["Shockwave Flash"]) {
            var swVer2 = navigator.plugins["Shockwave Flash 2.0"] ? " 2.0" : "";
            var flashDescription = navigator.plugins["Shockwave Flash" + swVer2].description;
            var descArray = flashDescription.split(" ");
            var tempArrayMajor = descArray[2].split(".");            
            var versionMajor = tempArrayMajor[0];
            var versionMinor = tempArrayMajor[1];
            var versionRevision = descArray[3];
            if (versionRevision == "") {
                versionRevision = descArray[4];
            }
            if (versionRevision[0] == "d") {
                versionRevision = versionRevision.substring(1);
            } else if (versionRevision[0] == "r") {
                versionRevision = versionRevision.substring(1);
                if (versionRevision.indexOf("d") > 0) {
                    versionRevision = versionRevision.substring(0, versionRevision.indexOf("d"));
                }
            }
            var flashVer = versionMajor + "." + versionMinor + "." + versionRevision;
        }
    }
    // MSN/WebTV 2.6 supports Flash 4
    else if (navigator.userAgent.toLowerCase().indexOf("webtv/2.6") != -1) flashVer = 4;
    // WebTV 2.5 supports Flash 3
    else if (navigator.userAgent.toLowerCase().indexOf("webtv/2.5") != -1) flashVer = 3;
    // older WebTV supports Flash 2
    else if (navigator.userAgent.toLowerCase().indexOf("webtv") != -1) flashVer = 2;
    else if ( isIE && isWin && !isOpera ) {
        flashVer = ControlVersion();
    }    
    return flashVer;
}

// When called with reqMajorVer, reqMinorVer, reqRevision returns true if that version or greater is available
function DetectFlashVer(reqMajorVer, reqMinorVer, reqRevision)
{
    versionStr = GetSwfVer();
    if (versionStr == -1 ) {
        return false;
    } else if (versionStr != 0) {
        if(isIE && isWin && !isOpera) {
            // Given "WIN 2,0,0,11"
            tempArray         = versionStr.split(" ");     // ["WIN", "2,0,0,11"]
            tempString        = tempArray[1];            // "2,0,0,11"
            versionArray      = tempString.split(",");    // ['2', '0', '0', '11']
        } else {
            versionArray      = versionStr.split(".");
        }
        var versionMajor      = versionArray[0];
        var versionMinor      = versionArray[1];
        var versionRevision   = versionArray[2];

            // is the major.revision >= requested major.revision AND the minor version >= requested minor
        if (versionMajor > parseFloat(reqMajorVer)) {
            return true;
        } else if (versionMajor == parseFloat(reqMajorVer)) {
            if (versionMinor > parseFloat(reqMinorVer))
                return true;
            else if (versionMinor == parseFloat(reqMinorVer)) {
                if (versionRevision >= parseFloat(reqRevision))
                    return true;
            }
        }
        return false;
    }
}

visto javascript não ser o meu forte fico com dúvidas se essas funções são ou não importantes...

[Procrastinator]

Dando uma olhadela rapido, percebe-se q essas funçoes sao usadas para detectar a versao do flash player. Se tiveres uma aplicaçao em flash q seja so para um determinado player suponho q possas usar essas funçoes para dar um aviso ao utilizador