port over article http://brett.is/writing/about/detect-flash-with-javascript

contents/writing/about/detect-flash-with-javascript/index.md

@@ -0,0 +1,62 @@
+---
+title: Detect Flash with JavaScript
+author: Brett Langdon
+date: 2013-06-05
+template: article.jade
+---
+
+Quick, easy and lightweight way to detecting flash support in clients.
+
+---
+
+Recently I had to find a a good way of detecting if <a href="http://www.adobe.com/products/flashplayer.html" target="_blank">Flash</a>
+is enabled in the browser, there are the two main libraries
+<a href="http://solutionpartners.adobe.com/products/flashplayer/download/detection_kit/" target="_blank">Adobe Flash Detection Kit</a>
+and <a href="https://code.google.com/p/swfobject/" target="_blank">SWFObject</a>
+which are both very good at detecting whether Flash is enabled as well as getting
+the version of Flash installed and useful for dynamically embedding and manipulating
+<a href="http://en.wikipedia.org/wiki/SWF" target="_blank">swf</a> files
+in your web application. But all I needed was a **yes** or a **no** to whether
+Flash was there or not without the added overhead of unneeded code.
+My goal was to wrote the least amount of JavaScript while still being able
+to detect cross browser for Flash.
+
+```javascript
+function detectflash(){
+    if (navigator.plugins != null && navigator.plugins.length > 0){
+        return navigator.plugins["Shockwave Flash"] && true;
+    }
+    if(~navigator.userAgent.toLowerCase().indexOf("webtv")){
+        return true;
+    }
+    if(~navigator.appVersion.indexOf("MSIE") && !~navigator.userAgent.indexOf("Opera")){
+        try{
+            return new ActiveXObject("ShockwaveFlash.ShockwaveFlash") && true;
+        } catch(e){}
+    }
+    return false;
+}
+```
+
+For those unfamiliar with the tilde (~) operator in javascript, please read
+<a href="http://dreaminginjavascript.wordpress.com/2008/07/04/28/" target="_blank">this article</a>,
+but the short version is, used with indexOf these two lines are equivalent:
+
+```javascript
+~navigator.appVersion.indexOf("MSIE")
+navigator.appVersion.indexOf("MSIE") != -1
+```
+
+To use the above function:
+
+```javascript
+if(detectflash()){
+    alert("Flash is enabled");
+} else{
+    alert("Flash is not available");
+}
+```
+
+And that is it. Pretty simple and a much shorter version that the alternatives,
+compressed and mangled I have gotten this code to under 400 Bytes.
+I tested this code with IE 5.5+, Firefox and Chrome without any issues.