Creating Message Handlers for the Property Sheet Elements

You need to add handlers to the design elements you have placed on the property page.

To create the message handlers

Double-click a design element on the property page. The following dialog box displays.
Select the design element name from the Class or object to handle list (for example, IDC_VIRUS_STRING).
Select the name of the event you want to handle (for example, the EN_CHANGE event).
Click the Add and Edit button – this will generate the needed method specification and let you edit the code. For example, if you use the IDC_VIRUS_STRING design element and the EN_CHANGE event, the following code will be generated:
```
LRESULT OnChange_VirusString(WORD wNotifyCode, WORD wID, HWND hWndCtl, BOOL& bHandled)
	{
		// TODO : Add Code for control notification handler.
		return 0;
}
```
You would like, at least, to enable the Apply button whenever a change to any of the controls is made. To do so you need to add the following code to the message handler:
```
	// Enable the Apply button
	SetModified();
```

Build date: 11/30/2009