How to read an OPC item value in Excel

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This is the simplest Excel VBA example. It reads an OPC item value and stores it in a cell of a worksheet.

Step 1: Create a new Excel worksheet, and select Developer -> Visual Basic from the ribbon:


Step 2. Select Tools -> References, check the box next to "OPC Labs EasyOPC Type Library", and press OK:


Step 3. Select This Workbook in the project tree, and then add a handler for opening the workbook by selecting Workbook and Open from the drop-downs on the top of he code window:


Step 4. Enter the code for the handler as follows:

   Private Sub Workbook_Open()
       ' Create EasyOPC-DA component
       Dim EasyDAClient As New EasyDAClient

       ' Read item value and display it
       Range("A1").Value = EasyDAClient.ReadItemValue("", "OPCLabs.KitServer.2", "Demo.Single")
   End Sub

As you can guess from the code, the event handler reads a value of an OPC Item (Demo.Single) and stores it into cell A1 of the worksheet.

Step 5. Save the file as "Excel Macro-Enabled Worksheet", close Excel, and then open the file again. The worksheet will read the OPC item and put it into cell A1, so you will see something like this:



This concept can obviously be enhanced in many different ways. Specifically, you may want to tie the OPC actions to different events, such as pressing a button on the sheet, or a periodic timer. This example project is included with the product. Please use the example from the product itself for the most up-to-date code of the example.