1 files changed, 29 insertions, 0 deletions
diff --git a/src/mscorlib/src/System/Collections/Generic/IReadOnlyDictionary.cs b/src/mscorlib/src/System/Collections/Generic/IReadOnlyDictionary.cs
new file mode 100644
index 0000000000..3603b9a4ea
--- /dev/null
+++ b/src/mscorlib/src/System/Collections/Generic/IReadOnlyDictionary.cs
@@ -0,0 +1,29 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+/*============================================================
+**
+** Interface:  IReadOnlyDictionary<TKey, TValue>
+** 
+** 
+**
+** Purpose: Base interface for read-only generic dictionaries.
+** 
+===========================================================*/
+using System;
+using System.Diagnostics.Contracts;
+
+namespace System.Collections.Generic
+{
+    // Provides a read-only view of a generic dictionary.
+    public interface IReadOnlyDictionary<TKey, TValue> : IReadOnlyCollection<KeyValuePair<TKey, TValue>>
+    {
+        bool ContainsKey(TKey key);
+        bool TryGetValue(TKey key, out TValue value);
+
+        TValue this[TKey key] { get; }
+        IEnumerable<TKey> Keys { get; }
+        IEnumerable<TValue> Values { get; }
+    }
+}