CODEWITHSUNDEEP
actionscript-3ioactionscripthttp-get
Joris Schellekens
Joris Schellekens

Reputation: 9012

How to catch Stream Error in ActionScript

I have the following piece of code, which attempts to GET a publicly hosted (AWS S3) file.

private function ShowS3Message():void
{
    // Attempt to download file from AWS
    var descriptor:XML = NativeApplication.nativeApplication.applicationDescriptor;
    var ns:Namespace = descriptor.namespaceDeclarations()[0];
    var url:String = "https://s3.amazonaws.com/some-url/file-" + descriptor.ns::versionLabel.split(".").join("-") + ".txt";
    var urlRequest:URLRequest = new URLRequest(url);

    // Set up callback function
    try{
        var loader:URLLoader = new URLLoader(); 
        loader.addEventListener(Event.COMPLETE, awsFetchCallback);                      
        loader.load(urlRequest);
    }catch(error:Error){}   
}

This is the callback function:

/**
 * Callback function for AWS message file
 */
private function awsFetchCallback(event:Event):void
{
    var data = event.target.data;

    // show dialog
    var msb:InformationMessageBox = new InformationMessageBox();
    msb.mText = data;
    msb.open(this, true);
}

When the file exists, there is no problem, and the code runs fine. When the file doesn't exist, this throws a StreamError, despite the catch block.

what am I missing?

Upvotes: 1

Views: 42

Answers (1)

C.Vergnaud
C.Vergnaud

Reputation: 877

You should capture the IO error event, there is not exception thrown when the file does not exist.

loader.addEventListener(IOErrorEvent.IO_ERROR, errorHandler);

and then create your own error handler function.

more details in the doc here : https://help.adobe.com/fr_FR/FlashPlatform/reference/actionscript/3/flash/net/URLLoader.html

If you just want to drown the error (because you seem to know the file may not exist sometimes) it is sufficient to create an empty error event handler.

Upvotes: 2

Related Questions