From 8604e142ca0d4a5e535895304e44f2945cea1243 Mon Sep 17 00:00:00 2001
From: Nasif Ishtiaque Islam <nasif.ishtiaque.islam@gmail.com>
Date: Sat, 4 Oct 2025 23:51:08 +0600
Subject: [PATCH]  Fix WriteDynamicHeader parameter to be non-nullable

 Changed WriteDynamicHeader method parameter from nullable IDynamicMetaObjectProvider? to non-nullable
  IDynamicMetaObjectProvider to fix issue #2355 with DynamicObject handling.
---
 src/CsvHelper/CsvWriter.cs | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/CsvHelper/CsvWriter.cs b/src/CsvHelper/CsvWriter.cs
index d74da342d..84bde24c5 100644
--- a/src/CsvHelper/CsvWriter.cs
+++ b/src/CsvHelper/CsvWriter.cs
@@ -296,7 +296,7 @@ public virtual void WriteHeader(Type type)
 	/// </summary>
 	/// <param name="record">The header record to write.</param>
 	/// <exception cref="ArgumentNullException">Thrown when no record is passed.</exception>
-	public virtual void WriteDynamicHeader(IDynamicMetaObjectProvider? record)
+	public virtual void WriteDynamicHeader(IDynamicMetaObjectProvider record)
 	{
 		if (record == null)
 		{
@@ -941,3 +941,4 @@ private bool WriteHeaderFromRecord(object? record)
 		return false;
 	}
 }
+