HwndSource.AddHook Method (HwndSourceHook)


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Adds an event handler that receives all window messages.

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

public void AddHook(
	HwndSourceHook hook


Type: System.Windows.Interop.HwndSourceHook

The handler implementation (based on the HwndSourceHook delegate) that receives the window messages.

System_CAPS_security Security Note

This method is not available in the Internet security zone.

Most Win32 messages that reach the HwndSource have an approximate WPF equivalent. You use AddHook to handle the cases where the message has no WPF equivalent.

The HwndSourceHook delegate resembles the parameter profile of a Win32 main window procedure. All window messages that the main window procedure of the HwndSource parent window receives are also forwarded to the HwndSourceHook delegates.

Hooks are called in the order that they were added. If any hook returns handled=true for a message, the hooks after it in the call order are not called for that message.


to add handling. Associated enumeration: AllWindows

.NET Framework
Available since 3.0
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