From e00a87fb126a1321637841dd013c282bd4e560b8 Mon Sep 17 00:00:00 2001
From: parallelbgls <parallelbgls@outlook.com>
Date: Thu, 4 Jan 2018 14:10:11 +0800
Subject: [PATCH] Fix

---
 Modbus.Net/Modbus.Net/MatchController.cs | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/Modbus.Net/Modbus.Net/MatchController.cs b/Modbus.Net/Modbus.Net/MatchController.cs
index 1ddc60c..02643ee 100644
--- a/Modbus.Net/Modbus.Net/MatchController.cs
+++ b/Modbus.Net/Modbus.Net/MatchController.cs
@@ -47,7 +47,12 @@ namespace Modbus.Net
         protected override MessageWaitingDef GetMessageFromWaitingList(byte[] receiveMessage)
         {
             var returnKey = GetKeyFromMessage(receiveMessage);
-            return WaitingMessages.FirstOrDefault(p=>returnKey.HasValue && p.Key == returnKey.Value.Item2);
+            MessageWaitingDef ans;
+            lock (WaitingMessages)
+            {
+                ans = WaitingMessages.FirstOrDefault(p => returnKey.HasValue && p.Key == returnKey.Value.Item2);
+            }
+            return ans;
         }
     }
 }