title: DDE Topic in VB.NET
body: <p>I have a VBA code in Excel which connects to a Rockwell PLC and collects data from PLC tag database.I defined a DDE topic in RSlinx Classic a software tool that comes with Rockwell software package and In the Excel Macro i have the following code    </p>
  
  <pre><code>Private Function OpenRSLinx()
  On Error Resume Next
  'Open the connection to RSLinx
  OpenRSLinx = DDEInitiate("RSLinx", "PLC")
  
  'Check if the connection was made
  If Err.Number &lt;&gt; 0 Then
      MsgBox "Error Connecting to topic", vbExclamation, "Error"
      OpenRSLinx = 0
  End If
  
  End Function
  
  Sub Check()  " This is my macro"
  rslinx = OpenRSLinx()
  
  Value = DDERequest(rslinx, "Tagname.Value") 
  </code></pre>
  
  <p>The code works perfectly so i was thinking about making it a VB.NET application but read that DDE topic is not supported on VB.NET.If DDE topic is not supported how can i achieve similar results with VB.Net.I have seen people mentioning about OPC but i don't have any experience with those. Can someone shed some light about a possible solution for my issue.</p>