This documentation is archived and is not being maintained.

WebBrowser.DetachSink Method

Releases the event-handling client attached in the CreateSink method from the underlying ActiveX control.

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

protected override void DetachSink()

This method is useful if you are familiar with OLE development using the unmanaged WebBrowser ActiveX control and you want to extend the functionality of the Windows Forms WebBrowser control, which is a managed wrapper for the ActiveX control. You can use this extensibility to implement events from the ActiveX control that are not provided by the wrapper control.

The following code example illustrates the use of this method in a class derived from WebBrowser that supplements the standard WebBrowser events with the NavigateError event from the OLE DWebBrowserEvents2 interface.

For the complete code example, see CreateSink.

AxHost.ConnectionPointCookie cookie;
WebBrowser2EventHelper helper;

[PermissionSetAttribute(SecurityAction.LinkDemand, Name="FullTrust")]
protected override void CreateSink()

    // Create an instance of the client that will handle the event
    // and associate it with the underlying ActiveX control.
    helper = new WebBrowser2EventHelper(this);
    cookie = new AxHost.ConnectionPointCookie(
        this.ActiveXInstance, helper, typeof(DWebBrowserEvents2));

[PermissionSetAttribute(SecurityAction.LinkDemand, Name="FullTrust")]
protected override void DetachSink()
    // Disconnect the client that handles the event
    // from the underlying ActiveX control.
    if (cookie != null)
        cookie = null;

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.