From 94adee0aaf0c482129d3dbb1cc42ea70e22767c5 Mon Sep 17 00:00:00 2001
From: sta <sta.blockhead@gmail.com>
Date: Mon, 17 Aug 2020 22:09:37 +0900
Subject: [PATCH] [Modify] Polish it

---
 websocket-sharp/Net/HttpListenerPrefixCollection.cs | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/websocket-sharp/Net/HttpListenerPrefixCollection.cs b/websocket-sharp/Net/HttpListenerPrefixCollection.cs
index cc70d2ff..450c2986 100644
--- a/websocket-sharp/Net/HttpListenerPrefixCollection.cs
+++ b/websocket-sharp/Net/HttpListenerPrefixCollection.cs
@@ -139,9 +139,8 @@ namespace WebSocketSharp.Net
     /// </exception>
     public void Add (string uriPrefix)
     {
-      _listener.CheckDisposed ();
-
       HttpListenerPrefix.CheckPrefix (uriPrefix);
+      _listener.CheckDisposed ();
 
       if (_prefixes.Contains (uriPrefix))
         return;