Hosting an ActiveX Control on a Windows Form
This topic demonstrates how to host the WebBrowser ActiveX control in a form by building an MDI WebBrowser application.
Windows Forms and ActiveX Controls
Windows Forms can only host Windows Forms controls. All Windows Forms controls are
classes that are derived from the System.Windows.Forms.Control class.
In order for an ActiveX control to be hosted on a form, it must appear like
a Windows Forms control. Conversely, an ActiveX control must appear to be
hosted in an ActiveX control container. The
System.Windows.Forms.AxHost class (which derives from
System.Windows.Forms.Control) acts as a Windows Forms control "on the
outside" and acts as an ActiveX control container "on the inside." In order to
host an ActiveX control, you must create a wrapper class
that derives from System.Windows.Forms.AxHost. This control hosts the
ActiveX control and exposes its properties, methods, and events (PMEs) as
PMEs of the generated conrtrol.
All conversions are done for an entire ActiveX control type library at the same time. You cannot use Aximp.exe to generate type information for a subset of the types defined within a single type library. The output of Aximp.exe is a set of binary files that contain the metadata and control implementation for the types defined within the original type library. The generated files are named according to the following pattern:
- common language runtime proxy for COM2 types: <PROGID>.dll
- Windows Forms proxy for ActiveX Controls: Ax<PROGID>.dll
You can examine these files with tools such as Metainfo.exe or Ildasm.exe.
Creating an ActiveX Control Wrapper
You create the the ActiveX control wrapper using the Aximp.exe tool included in the SDK. The following is an example of how to call Aximp.exe.
aximp c:\winnt\system32\shdocvw.dll
Using the Wrapper Control
Once you have created the control wrapper class you can use it in the same way that you would any Windows Forms control. The following example demonstrates how to add a WebBrowser control to a Form.
.... Imports AxSHDocVw .... AxWebBrowser1.BeginInit() .... AxWebBrowser1.Location = New System.Drawing.Point(0, 24) AxWebBrowser1.Size = New System.Drawing.Size(650, 456) AxWebBrowser1.Dock = System.Windows.Forms.DockStyle.Fill AxWebBrowser1.TabIndex = 3 .... Me.Controls.Add(AxWebBrowser1) .... AxWebBrowser1.EndInit() ....
Once you have finished writing the code for your form, you can build it and pass in references to the wrapper DLL files.
vbc.exe /nologo /t:exe /debug+ /R:System.DLL /R:System.Windows.Forms.DLL /R:System.Drawing.DLL /R:shdocvw.dll /R:AxShDocVw.DLL /out:MDIBrowser.exe MainForm.vb Document.vb
Web Browser Control Sample
The following sample demonstrates how to host an ActiveX control.
To view and run this sample.
[Run Sample] | [View Source] |