From 3d4c241c29be72c24d94b7c05e66ac81de456124 Mon Sep 17 00:00:00 2001
From: sta <sta.blockhead@gmail.com>
Date: Thu, 30 Apr 2020 20:04:54 +0900
Subject: [PATCH] [Modify] Replace it

---
 websocket-sharp/Net/WebHeaderCollection.cs | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/websocket-sharp/Net/WebHeaderCollection.cs b/websocket-sharp/Net/WebHeaderCollection.cs
index 3bb87b50..8a6159ad 100644
--- a/websocket-sharp/Net/WebHeaderCollection.cs
+++ b/websocket-sharp/Net/WebHeaderCollection.cs
@@ -1118,9 +1118,16 @@ namespace WebSocketSharp.Net
       if (header.Length == 0)
         throw new ArgumentException ("An empty string.", "header");
 
-      var pos = checkColonSeparated (header);
-      var name = header.Substring (0, pos);
-      var val = header.Substring (pos + 1);
+      var idx = header.IndexOf (':');
+
+      if (idx == -1) {
+        var msg = "No colon could be found.";
+
+        throw new ArgumentException (msg, "header");
+      }
+
+      var name = header.Substring (0, idx);
+      var val = header.Substring (idx + 1);
 
       add (name, val, false);
     }