FileDialog::HookProc Method (IntPtr, Int32, IntPtr, IntPtr)
Defines the common dialog box hook procedure that is overridden to add specific functionality to the file dialog box.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
protected: [SecurityPermissionAttribute(SecurityAction::LinkDemand, Flags = SecurityPermissionFlag::UnmanagedCode)] virtual IntPtr HookProc( IntPtr hWnd, int msg, IntPtr wparam, IntPtr lparam ) override
Parameters
- hWnd
-
Type:
System::IntPtr
The handle to the dialog box window.
- msg
-
Type:
System::Int32
The message received by the dialog box.
- wparam
-
Type:
System::IntPtr
Additional information about the message.
- lparam
-
Type:
System::IntPtr
Additional information about the message.
Return Value
Type: System::IntPtrReturns zero if the default dialog box procedure processes the message; returns a nonzero value if the default dialog box procedure ignores the message.
A hook procedure allows the user to connect or insert other routines into a routine or application for the purpose of debugging or enhancing functionality.
By default, the hook procedure centers the dialog box on the screen in response to a WM_INITDIALOG message.
Notes to Inheritors:
When overriding HookProc in a derived class, be sure to call the base class's HookProc method.
Available since 1.1