Microsoft KB Archive/190044

= PRB: Backspace in ATL Subclassed CTL Causes Internet Explorer to Navigate Back =

Article ID: 190044

Article Last Modified on 5/12/2003

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APPLIES TO


 * Microsoft Internet Explorer 3.02
 * Microsoft Internet Explorer 4.0 128-Bit Edition
 * Microsoft Internet Explorer 4.01 Service Pack 2
 * Microsoft Internet Explorer 4.01 Service Pack 1
 * Microsoft Internet Explorer 5.0
 * Microsoft Internet Explorer 5.01
 * Microsoft Internet Explorer (Programming) 5.01 SP1
 * Microsoft Internet Explorer 5.5

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This article was previously published under Q190044



SYMPTOMS
When an ATL ActiveX control that subclasses an edit control is hosted in Internet Explorer, pressing the BACKSPACE key when focus is set to the Edit control causes Internet Explorer to navigate to the previous Web page. If there are no Web pages previous to the one with the control, the BACKSPACE key functions as normal.



CAUSE
When the user clicks on the subclassed control, the control is not UI Activated. This means that any accelerator keys are processed by the Internet Explorer frame. The control is never given a change to process the BACKSPACE accelerator key.



RESOLUTION
When the user clicks in the edit box, a WM_MOUSEACTIVATE message is sent to the control. When this message is received, manually activate the control by calling CComControl::InPlaceActivate(OLEIVERB_UIACTIVATE).

Here is sample code for a WM_MOUSEACTIVATE handler that calls InPlaceActivate to manually UI Activate itself: LRESULT OnMouseActivate(UINT, WPARAM, LPARAM, BOOL&) {  // Manually activate the control InPlaceActivate(OLEIVERB_UIACTIVATE);

return 0; }



STATUS
This behavior is by design.

