The following example sets the ContentType property for the response to image/jpeg, calls the Clear method to remove other content that might be attached to the response, and then sets the BufferOutput property to true so that the complete page will be processed before any content is sent to the requesting client.
// Set the page's content type to JPEG files// and clears all content output from the buffer stream.
Response.ContentType = "image/jpeg";
// Buffer response so that page is sent// after processing is complete.
Response.BufferOutput = true;