diff --git a/aspnetcore/fundamentals/use-http-context.md b/aspnetcore/fundamentals/use-http-context.md index 6b0e0b6b26..e11443a8ff 100644 --- a/aspnetcore/fundamentals/use-http-context.md +++ b/aspnetcore/fundamentals/use-http-context.md @@ -99,6 +99,9 @@ An app can't modify headers after the response has started. Once the response st > System.InvalidOperationException: Headers are read-only, response has already started. +> [!NOTE] +> Unless response buffering is enabled, all write operations (for example, ) flush the response body internally and mark the response as started. Response buffering is disabled by default. + ### Write response body An HTTP response can include a response body. The response body is data associated with the response, such as generated web page content, UTF-8 JSON payload, or a file.