✨ CSharp event handler naming convention added

Author: alireza-mpr

csharp/README.md

@@ -7,5 +7,6 @@ List of covered sections:
 * [Method Naming](../csharp/method-naming.md)
 * [Variable Naming](../csharp/variable-naming.md)
 * [Namespaces Naming](../csharp/namespaces-naming.md)
+* [Event Handler Naming](../csharp/event-handler-naming.md)
 
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csharp/event-handler-naming.md

@@ -0,0 +1,12 @@
+# C# Naming Convention > Event Handler Naming
+
+## PascalCase
+- Capitalize first letter of each word of the event handler
+- Begin with the event name then suffix with `EventHandler`
+
+```c#
+private void ProductPurchasedEventHandler(object sender, ProductPurchasedEventArgs e)
+{
+    ...
+}
+```