From ac10a5912e72616c441253525b8cf74dd14877ad Mon Sep 17 00:00:00 2001
From: Oliver Booth <me@olivr.me>
Date: Sat, 16 Nov 2019 02:00:05 +0000
Subject: [PATCH] =?UTF-8?q?=E2=9C=A8=20Add=20StreamExtensions?=
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GetHash<T>() computes the hash of the given stream using the specified
hashing algorithm.
---
 X10D/StreamExtensions.cs | 30 ++++++++++++++++++++++++++++++
 X10D/X10D.csproj         |  1 +
 2 files changed, 31 insertions(+)
 create mode 100644 X10D/StreamExtensions.cs

diff --git a/X10D/StreamExtensions.cs b/X10D/StreamExtensions.cs
new file mode 100644
index 0000000..5576aca
--- /dev/null
+++ b/X10D/StreamExtensions.cs
@@ -0,0 +1,30 @@
+namespace X10D
+{
+    #region Using Directives
+
+    using System;
+    using System.IO;
+    using System.Reflection;
+    using System.Security.Cryptography;
+
+    #endregion
+
+    /// <summary>
+    /// A set of extension methods for <see cref="Stream"/>.
+    /// </summary>
+    public static class StreamExtensions
+    {
+        /// <summary>
+        /// Returns the hash of a stream using the specified hashing algorithm.
+        /// </summary>
+        /// <typeparam name="T">A <see cref="HashAlgorithm"/> derived type.</typeparam>
+        /// <param name="stream">The stream whose hash is to be computed.</param>
+        /// <returns>Returns a <see cref="Byte"/> array representing the hash of the stream.</returns>
+        public static byte[] GetHash<T>(this Stream stream) where T : HashAlgorithm
+        {
+            MethodInfo create = typeof(T).GetMethod("Create", new Type[] { });
+            using T    crypt  = (T)create?.Invoke(null, null);
+            return crypt?.ComputeHash(stream);
+        }
+    }
+}
diff --git a/X10D/X10D.csproj b/X10D/X10D.csproj
index 67c97df..841cc56 100644
--- a/X10D/X10D.csproj
+++ b/X10D/X10D.csproj
@@ -58,6 +58,7 @@
     <Compile Include="ListExtensions.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="RandomExtensions.cs" />
+    <Compile Include="StreamExtensions.cs" />
     <Compile Include="StringExtensions.cs" />
     <Compile Include="StructExtensions.cs" />
     <Compile Include="TimeSpanExtensions.cs" />