Handler file .ashx

The above Web. When the Default. This means you can map the default page in a directory to your handler.

Add example image. We mention what you can do with the ASHX file involving images. Find your favorite image on your disk or on the Internet and add it to your website project. For my example, the image I chose was "Flower1. Next We will use this image in the Handler. We implement an image-based handler. Modify Handler. Your handler has two parts. Here we modify the ProcessRequest method. We can change the ContentType of the file and the Response content.

Modify your Handler. Test handler. Here we test the new configuration and ASHX file on the local machine. Now click the green arrow to run your website on the development server.

You should see the image in your browser. This is the result of the handler. Add functionality. The example here so far is relatively useless. All it does is allow us to pipe an image through an ASHX handler. You can add any functionality logging code or referrer logic to the handler in the C language. Also, developers commonly need to use the QueryString collection on the Request.

You can use the Request. The code is the same. What this does. The above code receives requests and then returns a different file based on the QueryString collection value.

It will return one of two images from the two query strings. The strings it returns are shown. Notice that you have to include the IsReusable property. What does the code there do?

It defines two parts of the IHttpHandler interface. The important part is ProcessRequest , which will be invoked whenever the Handler. You can use the Request. Response; r. WriteFile "Arrow. WriteFile "Image. It will return one of two images from the two query strings. Add a comment. Active Oldest Votes. Just a few examples: Dynamic image generation : You can write handlers that return data driven images by creating an ASHX handler that returns image data and then using that URL in your tags.

Improve this answer. Mike Marshall Mike Marshall 7, 4 4 gold badges 37 37 silver badges 62 62 bronze badges. Can't I do 1 without a handler? I have that now but the aspx page does binary write.

Yes, aspx can do binary write but that is not what it is supposed to do. The primary purpose is to render HTML content. Yes, you can do 1 without a handler. Actually, you can do everything without a handler and just use an. But, the purpose of handlers is to identify the seperation of the Html view from 'some other type of data'.

Hence, my answer I posted seperately. NET pipleline stuff View State, control tree, etc that you'll never use. So, in the method like: mywebsite. They're very useful if your working in an environment where you do not have access to IIS but want to change things like far-future expiry response headers to optimize caching for files like css, images, JavaScript For images you can do stuff like on the fly optimization so you can request images like image.

Nick Allen Nick Allen For ashx file it is stateless. Unless you inherit it from IRequireSessionState to manage state. Use ashx for all Ajax calls and use aspx for purely asp. Pradeep Pradeep 1 1 1 bronze badge.