diff --git a/C# Coding Standards and Naming Conventions.md b/C# Coding Standards and Naming Conventions.md
index 8688f5b..4af11b6 100644
--- a/C# Coding Standards and Naming Conventions.md	
+++ b/C# Coding Standards and Naming Conventions.md	
@@ -412,6 +412,15 @@ public class BarcodeReadException : System.Exception
 }
 ```
 
+#### 26. Do use suffix Any, Is, Have or similar keywords for boolean identifier :
+
+```csharp 
+// Correct
+public static bool IsNullOrEmpty(string value) {
+    return (value == null || value.Length == 0);
+}
+```
+
 ***Why: consistent with the Microsoft's .NET Framework and easy to read.***
 
 ## Offical Reference