OPC UA数据采集（四）C# 的OpcUaHelper库连接opcua服务器

一、Nuget上添加OpcUaHelper库，要使用最新的版本2.2.1，旧版本亲测无法连接，比如版本2.1.3经过测试无法连接

二、代码

 class Program
 {
     static async Task Main(string[] args)
     {
         OpcUaClient opcUaClient = new OpcUaClient( );
         opcUaClient.OpcStatusChange += OpcUaClient_OpcStatusChange;

         try
         {
             await opcUaClient.ConnectServer("opc.tcp://localhost:4840");
         }
         catch (Exception ex)
         {
             Console.WriteLine( "Connect failed : " + ex.Message );
             return;
         }

         while (true)
         {
             Thread.Sleep( 1000 );
             try
             {
                 double value = opcUaClient.ReadNode<double>("ns=2;i=2");
                 Console.WriteLine("ns=2;i=2" + "   value: " + value );
             }
             catch (Exception ex)
             {
                 Console.WriteLine( "read failed: " + ex.Message );
             }
         }
     }

     private static void OpcUaClient_OpcStatusChange( object sender, OpcUaStatusEventArgs e )
     {
         Console.WriteLine( "OpcUaClient_OpcStatusChange: " + e.Error + " Text:" + e.Text );
     }
 }