diff --git a/SWIG/Examples/test-suite/csharp/operator_overload_runme.cs b/SWIG/Examples/test-suite/csharp/operator_overload_runme.cs
index 34439153e..711301a3b 100644
--- a/SWIG/Examples/test-suite/csharp/operator_overload_runme.cs
+++ b/SWIG/Examples/test-suite/csharp/operator_overload_runme.cs
@@ -6,11 +6,31 @@ public class runme
 {
   static void Main() 
   {
-    Op op = new Op(100);
-    op++;
-    if (op.i != 101) throw new Exception("operator++ failed");
-    op--;
-    if (op.i != 100) throw new Exception("operator-- failed");
+    Op.sanity_check();
+    {
+      Op op = new Op(100);
+      Op opNew = op++;
+      if (op.i != 101) throw new Exception("operator++ postfix failed (op)");
+      if (opNew.i != 100) throw new Exception("operator++ postfix failed (opNew)");
+    }
+    {
+      Op op = new Op(100);
+      Op opNew = op--;
+      if (op.i != 99) throw new Exception("operator-- postfix failed (op)");
+      if (opNew.i != 100) throw new Exception("operator-- postfix failed (opNew)");
+    }
+    {
+      Op op = new Op(100);
+      Op opNew = ++op;
+      if (op.i != 101) throw new Exception("operator++ prefix failed (op)");
+      if (opNew.i != 101) throw new Exception("operator++ prefix failed (opNew)");
+    }
+    {
+      Op op = new Op(100);
+      Op opNew = --op;
+      if (op.i != 99) throw new Exception("operator-- prefix failed (op)");
+      if (opNew.i != 99) throw new Exception("operator-- prefix failed (opNew)");
+    }
   }
 }