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When I try to use getEventListeners in puppeteerSharp I got getEventListeners is not defined error:

var result = await page.EvaluateExpressionHandleAsync("getEventListeners(document.forms[0].getElementsByTagName('button')[0])");
How to use getEventListeners within puppeteerSharp?
I found this for javascript:
const cdp = await page.target().createCDPSession();    
const listeners = await cdp.send('DOMDebugger.getEventListeners', { objectId });
and I tried to convert it back into C#:
var t = await page.EvaluateExpressionHandleAsync(@"document.forms[0].getElementsByTagName('button')[0]");
var client = await page.Target.CreateCDPSessionAsync();
var result = await client.SendAsync("DOMDebugger.getEventListeners", t.RemoteObject.ObjectId);
but it seems I'm doing something wrong and I did not find any clear documentation about this.
                getEventListeners is a console utility that is not an available function to use in a script developers.google.com/web/tools/chrome-devtools/console/…
– hardkoded
                Feb 20, 2021 at 16:44
                @hardkoded here: stackoverflow.com/questions/63059096/… in the first answer, it seems he uses getEventListeners. but I do not know how to convert it back into c#
– Inside Man
                Feb 21, 2021 at 3:25
I have found the solution, here it is for those who may be interested:
First, we should create a CDPSession like this:
var client = await page.Target.CreateCDPSessionAsync();
then we should Evaluate our script to get an element:
var body = await client.SendAsync("Runtime.evaluate", new { expression = "document.getElementsByTagName('input')[0]" });
and at last, we should use DOMDebugger with the element's objectId to get its event listeners:
var result = await client.SendAsync("DOMDebugger.getEventListeners", new { objectId = body["result"]["objectId"] });
        
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