From 1cadc54c3b3fca71fcabd90965d2dd76ad1ebaf0 Mon Sep 17 00:00:00 2001
From: Kiran Challa <kichalla@microsoft.com>
Date: Thu, 30 Apr 2015 12:43:49 -0700
Subject: [PATCH] Use TryAdd to add services rather than Add

---
 .../CorsServiceCollectionExtensions.cs                        | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/Microsoft.AspNet.Cors.Core/CorsServiceCollectionExtensions.cs b/src/Microsoft.AspNet.Cors.Core/CorsServiceCollectionExtensions.cs
index 544b426837..11c1b5261a 100644
--- a/src/Microsoft.AspNet.Cors.Core/CorsServiceCollectionExtensions.cs
+++ b/src/Microsoft.AspNet.Cors.Core/CorsServiceCollectionExtensions.cs
@@ -35,8 +35,8 @@ namespace Microsoft.Framework.DependencyInjection
         public static IServiceCollection AddCors(this IServiceCollection serviceCollection)
         {
             serviceCollection.AddOptions();
-            serviceCollection.AddTransient<ICorsService, CorsService>();
-            serviceCollection.AddTransient<ICorsPolicyProvider, DefaultCorsPolicyProvider>();
+            serviceCollection.TryAdd(ServiceDescriptor.Transient<ICorsService, CorsService>());
+            serviceCollection.TryAdd(ServiceDescriptor.Transient<ICorsPolicyProvider, DefaultCorsPolicyProvider>());
             return serviceCollection;
         }
     }