WindowInteropHelper Class

WindowInteropHelper Class


Assists interoperation between Windows Presentation Foundation (WPF) and Win32 code. 

Namespace:   System.Windows.Interop
Assembly:  PresentationFramework (in PresentationFramework.dll)


public sealed class WindowInteropHelper


Initializes a new instance of the WindowInteropHelper class for a specified Windows Presentation Foundation (WPF) window. 


Gets the window handle for a Windows Presentation Foundation (WPF) window that is used to create this WindowInteropHelper.


Gets or sets the handle of the Windows Presentation Foundation (WPF) owner window.


Creates the HWND of the window if the HWND has not been created yet.


Determines whether the specified object is equal to the current object.(Inherited from Object.)


Serves as the default hash function. (Inherited from Object.)


Gets the Type of the current instance.(Inherited from Object.)


Returns a string that represents the current object.(Inherited from Object.)

Members of this class allows the caller to have internal access to the Win32 HWND and the parent HWND of a WPF Window.  The proper security checks are performed by those members.

Use this class whenever you need a more specific object based on its HWND.

An example scenario is if you need to host a WPF dialog box in a Win32 application. Initialize the WindowInteropHelper with a WPF window object for the dialog box. You can then get the WPF window's handle (HWND) from the Handle property and specify the owner for the WPF window with the Owner property. The following code example shows how to use WindowInteropHelper when hosting a WPF dialog box in a Win32 application.

WindowInteropHelper wih = new WindowInteropHelper(myDialog);
wih.Owner = ownerHwnd;

Another scenario supported by this class is to obtain a HwndSource object from a WPF Window object. The HwndSource enables direct processing of Win32 messages through the AddHook method. By using HwndSource and AddHook in place of a Window you can still handle messages that have no equivalent or handling in WPF. Create a WindowInteropHelper with the Window source, then call Handle on the WindowInteropHelper to get from HWND to HwndSource.

.NET Framework
Available since 3.0

Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

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