add explicit null check for older target frameworks

DataDog · Jan 10, 2024 · 3e1938e · 3e1938e
1 parent 47835f2
commit 3e1938e
Showing 1 changed file with 1 addition and 1 deletion.
diff --git a/tracer/src/Datadog.Trace/Sampling/SamplingRulesFormat.cs b/tracer/src/Datadog.Trace/Sampling/SamplingRulesFormat.cs
@@ -19,7 +19,7 @@ internal static class SamplingRulesFormat
 
     public static bool IsValid(string? format, out string normalized)
     {
-        if (string.IsNullOrWhiteSpace(format))
+        if (format is null || string.IsNullOrWhiteSpace(format))
         {
             // default value if not specified
             normalized = Regex;