From 59f51380a63b9a143b2a1441c3a6427762fe59db Mon Sep 17 00:00:00 2001
From: sta <sta.blockhead@gmail.com>
Date: Wed, 12 Dec 2018 20:19:15 +0900
Subject: [PATCH] [Modify] Throw exception

---
 websocket-sharp/Net/HttpUtility.cs | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/websocket-sharp/Net/HttpUtility.cs b/websocket-sharp/Net/HttpUtility.cs
index e3098289..df7b3b90 100644
--- a/websocket-sharp/Net/HttpUtility.cs
+++ b/websocket-sharp/Net/HttpUtility.cs
@@ -945,7 +945,10 @@ namespace WebSocketSharp.Net
 
     public static string UrlDecode (string s, Encoding encoding)
     {
-      if (s == null || s.Length == 0 || !s.Contains ('%', '+'))
+      if (s == null)
+        throw new ArgumentNullException ("s");
+
+      if (s.Length == 0)
         return s;
 
       if (encoding == null)