Response.Flush: Forces all currently buffered output to be sent to the client. The Flush method can be called multiple times during request processing. but is not stop the processing of the page, so it will continue the execution of the next steps.
Sends all currently buffered output to the client, stops execution of the page, and raises the EndRequest event.
Also, your question is more related with HttpResponse, I suggest you can visit the ASP.NET forum
for getting suitable help.
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