From e6b1a52e9306317b86f75314d90ffeab23f1607a Mon Sep 17 00:00:00 2001 From: Copilot <198982749+Copilot@users.noreply.github.com> Date: Thu, 6 Nov 2025 20:31:50 +0000 Subject: [PATCH] Document MultipartContent zero-part serialization behavior (#12014) Co-authored-by: copilot-swe-agent[bot] <198982749+Copilot@users.noreply.github.com> Co-authored-by: MihaZupan <25307628+MihaZupan@users.noreply.github.com> Co-authored-by: Miha Zupan Co-authored-by: Genevieve Warren <24882762+gewarren@users.noreply.github.com> --- xml/System.Net.Http/MultipartContent.xml | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/xml/System.Net.Http/MultipartContent.xml b/xml/System.Net.Http/MultipartContent.xml index 396d5496c45..09558f5679f 100644 --- a/xml/System.Net.Http/MultipartContent.xml +++ b/xml/System.Net.Http/MultipartContent.xml @@ -52,7 +52,10 @@ Provides a collection of objects that get serialized using the multipart/* content type specification. - To be added. + +Multipart messages must contain one or more body parts. When a instance with zero parts is serialized, it's written as a single empty part with no content headers or message body. +If your server doesn't support such contents with zero parts, consider conditionally using a different type or no . +