Add code example for CA1700 rule (#48932)

docs/fundamentals/code-analysis/quality-rules/ca1700.md

@@ -10,6 +10,8 @@ helpviewer_keywords:
 - CA1700
 author: gewarren
 ms.author: gewarren
+dev_langs:
+- CSharp
 ---
 # CA1700: Do not name enum values 'Reserved'
 
@@ -43,6 +45,10 @@ In a limited number of cases the addition of a member is a breaking change even
 
 To fix a violation of this rule, remove or rename the member.
 
+## Example
+
+:::code language="csharp" source="snippets/csharp/all-rules/ca1700.cs" id="snippet1":::
+
 ## When to suppress warnings
 
 It is safe to suppress a warning from this rule for a member that is currently used or for libraries that have previously shipped.

docs/fundamentals/code-analysis/quality-rules/snippets/csharp/all-rules/ca1700.cs

@@ -0,0 +1,22 @@
+namespace ca1700
+{
+    //<snippet1>
+    // This class violates the rule.
+    public enum BadPaymentStatus
+    {
+        Pending = 0,
+        Completed = 1,
+        ReservedError = 2,
+        Reserved = 3,
+    }
+
+    // This class satisfies the rule.
+    public enum GoodPaymentStatus
+    {
+        Pending = 0,
+        Completed = 1,
+        Error = 2,
+        Unknown = 3,
+    }
+    //</snippet1>
+}