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Flash Player Article

 

Future-Proofing Flash Player Detection Scripts


Table of Contents

  1. Introduction
  2. Checking for More Than Just the Version You Need
  3. The Right Way to Detect

The Right Way to Detect

In order to detect the existence of Flash Player at all, you will need to use small amounts of JavaScript and VBScript. The following script determines the existence and version information of the Flash Player ActiveX control:

<script language="VBScript">
<!-- // Visual basic helper required to detect Flash Player ActiveX control version information
      Function VBGetSwfVer(i)
        on error resume next
        Dim swControl, swVersion
        swVersion = 0
        
        set swControl = CreateObject("ShockwaveFlash.ShockwaveFlash." + CStr(i))
        if (IsObject(swControl)) then
          swVersion = swControl.GetVariable("$version")
        end if
        VBGetSwfVer = swVersion
      End Function
// -->
</script>

By calling the VBGetSwfVer(i) function with the required major version, you will locate two important pieces of information–the existence of Flash Player and its version:

  • swControl: true or false, depending on whether Flash Player is installed or not
  • swVersion: full version string (for example, "WIN 7,0,14,0") if Flash Player is installed

The following script determines the existence and version information of the Flash Player plug-in. This applies to Netscape, Firefox, Mozilla, Safari, Opera, and all other browsers that support the Netscape Plug-in API and a way to interrogate it using browser scripting:

<SCRIPT LANGUAGE="JavaScript" type="text/javascript">
<!-- // Detect Client Browser type
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;

// JavaScript helper required to detect Flash Player PlugIn version information
function JSGetSwfVer(i){
      // NS/Opera version >= 3 check for Flash plugin in plugin array
      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;
                        descArray = flashDescription.split(" ");
                        tempArrayMajor = descArray[2].split(".");
                        versionMajor = tempArrayMajor[0];
                  if ( descArray[3] != "" ) {
                        tempArrayMinor = descArray[3].split("r");
                  } else {
                        tempArrayMinor = descArray[4].split("r");
                  }
                        versionMinor = tempArrayMinor[1] > 0 ? tempArrayMinor[1] : 0;
                        flashVer = parseFloat(versionMajor + "." + versionMinor);
            } else {
                  flashVer = -1;
            }
      }
      // 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;
      // Can't detect in all other cases
      else {
            
            flashVer = -1;
      }
      return flashVer;
}
/ -->
</script>

After you determine which browser your script is running, run through each of these scripts until you find the latest version of the player installed.

The following script starts with a high version number (25) and runs through the proper script for each potential version to determine if it exists on the client. Once the script gets a valid return value, it sets the value of versionStr to the installed version:

// loop backwards through the versions until we find the newest version      
for (i=25;i>0;i--) {      
if (isIE && isWin && !isOpera) {
      versionStr = VBGetSwfVer(i);
} else {
      versionStr = JSGetSwfVer(i);
}

At this point you can take this value and make sure your content can be displayed properly in the browser. For example, if your content requires Flash Player 6r65, you could use the following script in conjunction with the scripts above to determine if the client has Flash Player and the proper version:

// If called with no parameters this function returns a floating point value 
// which should be the version of the Flash Player or 0.0 
// ex: Flash Player 6r65 returns 6.65
// If called with reqMajorVer, reqMinorVer this function returns true if that version or greater is installed
function DetectFlashVer(reqMajorVer, reqMinorVer) 
{
      reqVer = parseFloat(reqMajorVer + "." + reqMinorVer);
      // loop backwards through the versions until we find the newest version      
      for (i=25;i>0;i--) {      
            if (isIE && isWin && !isOpera) {;
                  versionStr = VBGetSwfVer(i);
            } else {
                  versionStr = JSGetSwfVer(i);
            }
            if (versionStr == -1) {
					return false;
			  } else if (versionStr != 0) {
                  if(isIE && isWin && !isOpera) {
                        tempArray = versionStr.split(" ");
                        tempString = tempArray[1];
                        versionArray = tempString .split(",");
                        
                        versionMajor = versionArray[0];
                        versionMinor   = versionArray[2];
                        
                        versionString = versionMajor + "." + versionMinor;
                        versionNum = parseFloat(versionString);
                  } else {
                         versionNum = versionStr;
                  }
                  return (versionNum >= reqVer ? true : false );            
            }
      }
      
      return (reqVer ? false : 0.0);
}

To detect for a specific version of the player, you would call DetectFlashVer(reqMajorVer, reqMinorVer). When calling DetectFlashVer(), pass it a number for reqMajorVer and reqMinorVer. For example, if you want to make sure the end user has Flash Player 6r65 you would enter:

var hasCorrectVersion = DetectFlashVer(6, 65);

If the client has the correct major and minor version (or greater) the variable hasCorrectVersion will equal true. If Flash Player is not installed or the version does not meet the requirements you have specified, it will return false. In addition, if you call DetectFlashVer() with no parameters, you will get a value for the installed player version. If the client has Flash Player 6r65 installed, calling DetectFlashVer() will return "6.65".

Once you complete your script, you will know everything you need to perform proper player detection: whether Flash Player is installed and what version it is. Now your code is future-proof!

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