From 8f2d5a593a28bdb84c16d3a85f3ca111b8ece9b5 Mon Sep 17 00:00:00 2001
From: sta <sta.blockhead@gmail.com>
Date: Mon, 25 Dec 2017 04:38:58 +0900
Subject: [PATCH] [Modify] Add it

---
 websocket-sharp/Ext.cs | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/websocket-sharp/Ext.cs b/websocket-sharp/Ext.cs
index 0f1ab909..4bf90ac9 100644
--- a/websocket-sharp/Ext.cs
+++ b/websocket-sharp/Ext.cs
@@ -597,6 +597,16 @@ namespace WebSocketSharp
       return true;
     }
 
+    internal static bool KeepsAlive (
+      this NameValueCollection headers, Version version
+    )
+    {
+      var comparison = StringComparison.OrdinalIgnoreCase;
+      return version < HttpVersion.Version11
+             ? headers.Contains ("Connection", "keep-alive", comparison)
+             : !headers.Contains ("Connection", "close", comparison);
+    }
+
     internal static string Quote (this string value)
     {
       return String.Format ("\"{0}\"", value.Replace ("\"", "\\\""));