Flash / ActionScript 3 / Flex : Reading browser cookies

Part of an ActionScript 3 project I was working on required me to pull cookies from the users browser into Flash. I tried hunting around google to find a good method to achieve this, but found a lot of articles that wanted you to alter the embed code for flash. I wanted to find a way inside Flash to read the users cookies.

I wrote some code to do something similar in ActionScript 2 that used LoadVars. This class has been removed in ActionScript 3.

This is the ActionScript 3 code I came up with. It uses ExternalInterface to execute a bit of javascript that will pull the cookies directly into flash. It alters the cookie string to make it look like a URL and runs it through URLVariables.

package {
    import flash.display.Sprite;
    import flash.external.ExternalInterface;
    import flash.net.URLVariables;
    
    public class BrowserCookies extends Sprite
    {
        //this will parse the cookie data
        private var _urlVariables:URLVariables;
        
        /**
         * Return all the cookie values in one object
         * @return URLVariables 
         * 
         */
        public function get urlVariables() : URLVariables {
            return _urlVariables;
        }
        
        /**
         * Return one cookie value
         * @param value String
         * @return String
         * 
         */
        public function getCookieValue(value:String) : String {
            var returnValue:String = "";
            
            if(_urlVariables && _urlVariables[value]) {
                returnValue = _urlVariables[value];
            }
            
            return returnValue;
        }
        
        /**
         * This will connect to the browser and pull cookies into flash 
         */
        public function BrowserCookies() : void{
            //this will hold the data returned from javascript
            var browserCookieString:String;
            
            //pull the data from javascript
            browserCookieString = ExternalInterface.call("function(){return document.cookie}");
            
            //replace ; with & to make it look like a url
            browserCookieString = browserCookieString.replace(/;\s/g, "&");

            //parse the cookie string into variables. you can now access cookie variables as properties of this object
            if(browserCookieString) {
                _urlVariables = new URLVariables(browserCookieString);
            }
        }
    }
}

Now you can access any cookie property inside flash. Here is a quick example of how to use the class. Assume BrowserCookies.as exists in the same folder as the example class.

package
{
    import flash.display.Sprite;
    import flash.text.TextField;
    
    public class Index extends Sprite{
        public function Index(){
            //this will pull all the cookies out of the browser
            var urlVars:BrowserCookies = new BrowserCookies;
            var textField:TextField = new TextField;
            
            textField.width = 200;
            textField.height = 200;
            textField.text = urlVars.getCookieValue("today");
            
            addChild(textField);
        }
    }
}

I've uploaded a Flex Projext Export version of this example available here. Feel free to contact me if you have any questions.