From e2f2ffa870cdfc3c54435ff5243d5db2c1e89d50 Mon Sep 17 00:00:00 2001
From: Elzo Lubbers <elzo.lubbers@stater.nl>
Date: Fri, 2 Feb 2024 15:49:00 +0100
Subject: [PATCH] Apply ParameterDateFormat to date in header as well

---
 .../Templates/Client.Class.HeaderParameter.liquid             | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/src/NSwag.CodeGeneration.CSharp/Templates/Client.Class.HeaderParameter.liquid b/src/NSwag.CodeGeneration.CSharp/Templates/Client.Class.HeaderParameter.liquid
index 9d686c515d..571aa4e388 100644
--- a/src/NSwag.CodeGeneration.CSharp/Templates/Client.Class.HeaderParameter.liquid
+++ b/src/NSwag.CodeGeneration.CSharp/Templates/Client.Class.HeaderParameter.liquid
@@ -1,7 +1,9 @@
 {% if parameter.IsStringArray -%}
 request_.Headers.TryAddWithoutValidation("{{ parameter.Name }}", {{ parameter.VariableName }});
 {% elsif parameter.IsDateTime -%}
-request_.Headers.TryAddWithoutValidation("{{ parameter.Name }}", ConvertToString({{ parameter.VariableName }}{% if parameter.IsNullable %}?{% endif %}.ToString("{{ ParameterDateTimeFormat }}"), System.Globalization.CultureInfo.InvariantCulture));
+request_.Headers.TryAddWithoutValidation("{{ parameter.Name }}", ConvertToString({{ parameter.VariableName }}{% if parameter.IsNullable or parameter.IsSystemNullable %}?{% endif %}.ToString("{{ ParameterDateTimeFormat }}"), System.Globalization.CultureInfo.InvariantCulture));
+{% elsif parameter.IsDate -%}
+request_.Headers.TryAddWithoutValidation("{{ parameter.Name }}", ConvertToString({{ parameter.VariableName }}{% if parameter.IsNullable or parameter.IsSystemNullable %}?{% endif %}.ToString("{{ ParameterDateFormat }}"), System.Globalization.CultureInfo.InvariantCulture));
 {% else -%}
 request_.Headers.TryAddWithoutValidation("{{ parameter.Name }}", ConvertToString({{ parameter.VariableName }}, System.Globalization.CultureInfo.InvariantCulture));
 {%- endif %}