Host an OCX control within a .Net windows application-.Net and COM part IV

In this article I will explain how to host an OCX control within a .Net application.

I invite you to follow those steps to perform that.


  1. Create an OCX customized control, either using Visual C++6.0 or Visual Basic 6.0 or download one from the internet, any one because the purpose here is to step through the manner of hosting it within a given Windows .Net application. (In my case, I ran the research on local machine for a given OCX and I have chosen the MSFlexGrid.ocx control and a testing control.

  2. Copy and paste your control in the root drive say the C:\ 
  3. Open the command prompt by browsing to Start>All programs>Accessory>Command prompt then type those couple of lines as bellow:


    The aximp that stands for ActiveX Control Importer is used in this case. It does the conversion type definitions according to COM type library for an OCX control into a standard Windows Forms control. Because Windows Forms can only host Windows Forms controls and not any other control types at any cases including the OCX ones, Of Corse. Aximp.exe generates a wrapper like the RCW the runtime callable wrapper class for an ActiveX control that can be hosted on a Windows Form. This is the only way that allows the OCX use.

    As the figure above shows, there is a new generated dll called MSFlexGridLib.dll located in C:\Program Files\Microsoft SDKs\Windows\v6.0A\Bin.

  4. Create a new Windows application project.

  5. Add a reference to this dll by going to the solution explorer, right clicking on the project and selecting Add reference menu item.

    Figure 1

  6. Select browse tab as follow :

    Figure 2

  7. As you can remark, the reference to your new generated dll is added.

    Figure 3

  8. Now, add the namespace using AxMSFlexGridLib; then add this couple of code within the load event handler
    stub as under:

    void Form1_Load(object sender, EventArgs e)
            AxMSFlexGrid oGrid = new AxMSFlexGrid();
            oGrid.Visible = true;
            oGrid.Parent = this;
            oGrid.Dock = DockStyle.Fill;
            oGrid.CellBackColor = Color.Bisque;
            oGrid.Cols = 7;
            oGrid.Rows = 30;

  9. Finally, run the application.

    Figure 4
That's it
Good Dotneting !!!