AxHost::AttachInterfaces Method ()


When overridden in a derived class, attaches interfaces to the underlying ActiveX control.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

virtual void AttachInterfaces()

Notes to Inheritors:

Classes that extend AxHost should override this method. Within an overridden version of this method, the extending class should call GetOcx to retrieve its own interface. In most cases, the GetOcx method should not be called before this method is called.

The following code example overrides the constructor, and the SetAboutBoxDelegate and AttachInterfaces methods of an AxHost derived class that wraps the Microsoft Masked Edit ActiveX Control. This code requires that you have created the generated source code by running the AxImp.exe on the MSMask32.ocx file with the /source switch to generate the wrapper class to be edited. This code is only shown in C# syntax because that is the only language output by the AxImp.exe.

public AxMaskEdBox()
  base("c932ba85-4374-101b-a56c-00aa003668dc") // The ActiveX control's class identifier.
    // Make the AboutBox method the about box delegate.
    this.SetAboutBoxDelegate(new AboutBoxDelegate(AboutBox));

public virtual void AboutBox()
    // If the instance of the ActiveX control is null when the AboutBox method 
    // is called, raise an InvalidActiveXStateException exception.
    if ((this.ocx == null))
        throw new System.Windows.Forms.AxHost.InvalidActiveXStateException(
          "AboutBox", System.Windows.Forms.AxHost.ActiveXInvokeKind.MethodInvoke);
    // Show the about box if the ActiveX control has one.
    if (this.HasAboutBox)

protected override void AttachInterfaces()
        // Attach the IMSMask interface to the ActiveX control.
        this.ocx = ((MSMask.IMSMask)(this.GetOcx()));
    catch (System.Exception ex)

.NET Framework
Available since 1.1
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