7 Answers, 1 is accepted
Hello Herson,
You could use FiddlerScript and its events to modify headers and/or the body content of any request and response. In this documentation article, you will find multiple examples of using FiddlerScript and many of the build-in methods to modify HTTP requests and responses.
Regards,
Nick Iliev
Progress Telerik
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Hi. Thanks. I tried this but nothing happens.
if (oSession.uriContains("mysitefile.json") && oSession.oResponse.headers.ExistsAndContains("Content-Type","text/html")){ oSession.utilDecodeResponse(); oSession.utilReplaceInResponse('eight:100%','eight:5%');}
Hello Herson,
It is hard to pinpoint what exactly might be happening on your side. You could try to isolate the issue by providing the minimum code sample required to reproduce the case (alongside the used endpoint and details about the expected outcome).
You could also check if you are able to make a more cardinal change - for example try to entirely replace an Image or add new title to the very same response you are trying to modify (to test if you are able to hit the oSession conditions in the script).
Regards,
Nick Iliev
Progress Telerik
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Hеy Herson,
Have you tried using the onBeforeResponse event in FiddlerScript (see more here)? Your screenshot doesn't provide much information about the actual FiddlerScript code and the endpoints you might have used which is why we.ve asked for a code sample of the things you have tried so far.
Here is a very basic example, on how to change the HTML content in a received response from example.com
- Open FiddlerScript tab and make the response modification in onBeforeResponse event. In the example below, I am checking the session URL and if a specific header exists and then changing the H1 title to H3 with italic font.
static function OnBeforeResponse(oSession: Session) {
if (oSession.uriContains("example") && oSession.oResponse.headers.ExistsAndContains("Content-Type","text/html")) {
oSession.utilDecodeResponse();
oSession.utilReplaceInResponse('<h1>','<h3><em>');
oSession.utilReplaceInResponse('</h1>','</em></h3>');
}
}
- Use Save Script after applying the changes
- Open you browser (or use the Composer) and navigate to the example.com page.
As a result, you should now see a smaller title with italic style.
Regards,
Nick Iliev
Progress Telerik
Love the Telerik and Kendo UI products and believe more people should try them? Invite a fellow developer to become a Progress customer and each of you can get a $50 Amazon gift voucher.

Hеy Herson,
Have you tried using the onBeforeResponse event in FiddlerScript (see more here)? Your screenshot doesn't provide much information about the actual FiddlerScript code and the endpoints you might have used which is why we.ve asked for a code sample of the things you have tried so far.
Here is a very basic example, on how to change the HTML content in a received response from example.com
- Open FiddlerScript tab and make the response modification in onBeforeResponse event. In the example below, I am checking the session URL and if a specific header exists and then changing the H1 title to H3 with italic font.
static function OnBeforeResponse(oSession: Session) {
if (oSession.uriContains("example") && oSession.oResponse.headers.ExistsAndContains("Content-Type","text/html")) {
oSession.utilDecodeResponse();
oSession.utilReplaceInResponse('<h1>','<h3><em>');
oSession.utilReplaceInResponse('</h1>','</em></h3>');
}
}
- Use Save Script after applying the changes
- Open you browser (or use the Composer) and navigate to the example.com page.
As a result, you should now see a smaller title with italic style.
Regards,
Nick Iliev
Progress Telerik
Love the Telerik and Kendo UI products and believe more people should try them? Invite a fellow developer to become a Progress customer and each of you can get a $50 Amazon gift voucher.