Control.WndProc Method (Message)

 
System_CAPS_noteNote

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Processes Windows messages.

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

[<SecurityPermissionAttribute(SecurityAction.InheritanceDemand,
    Flags = SecurityPermissionFlag.UnmanagedCode)>]
[<SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode)>]
abstract WndProc : 
        m:Message byref -> unit
[<SecurityPermissionAttribute(SecurityAction.InheritanceDemand,
    Flags = SecurityPermissionFlag.UnmanagedCode)>]
[<SecurityPermissionAttribute(SecurityAction.LinkDemand, Flags = SecurityPermissionFlag.UnmanagedCode)>]
override WndProc : 
        m:Message byref -> unit

Parameters

m
Type: System.Windows.Forms.Message

The Windows Message to process.

All messages are sent to the WndProc method after getting filtered through the PreProcessMessage method.

The WndProc method corresponds exactly to the Windows WindowProc function. For more information about processing Windows messages, see the WindowProc function.

Notes to Inheritors:

Inheriting controls should call the base class's WndProc method to process any messages that they do not handle.

The following code example demonstrates overriding the WndProc method to handle operating system messages identified in the Message structure. TheWM_ACTIVATEAPPoperating system message is handled in this example to know when another application is becoming active. See the following topics to understand the available Message.Msg, Message.LParam, and Message.WParam values. Actual constant values can be found in the Windows.h header file.

No code example is currently available or this language may not be supported.

SecurityPermission

for inheriting classes to call unmanaged code. Associated enumeration: SecurityPermissionFlag.UnmanagedCode.

SecurityPermission

for the immediate caller to call unmanaged code. Associated enumeration: SecurityPermissionFlag.UnmanagedCode.

.NET Framework
Available since 1.1
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