PSM_CANCELTOCLOSE message

Sent by an application when it has performed changes since the most recent PSN_APPLY notification that cannot be canceled. You can send this message explicitly or by using the PropSheet_CancelToClose macro.

Parameters

wParam

Must be zero.

lParam

Must be zero.

Return value

No return value.

Remarks

PSM_CANCELTOCLOSE disables the Cancel button and changes the text of the OK button to "Close".

Most property sheets wait to perform irreversible changes until a PSN_APPLY notification is received. However, in some circumstances, a property sheet may make irreversible changes outside the standard PSN_APPLY/PSN_RESET sequence. One example is a property sheet that contains an Edit button that is used to display a subdialog box for editing a property. When the user clicks OK to submit the change, the property sheet page has several options.

• It can record the changes, but wait until it receives a PSN_APPLY notification to apply them. This is the preferred approach.
• It can apply the changes immediately after exiting the subdialog box, but remember the original settings. Those settings can be used to restore the original state if a PSN_RESET notification is received.
• It can apply the changes immediately and not attempt to restore the original settings when it receives a PSN_RESET notification. This approach is not recommended, but may be necessary if the changes are too far-reaching for the other two options to be practical.

For the third option, applications should send a PSM_CANCELTOCLOSE message to the property sheet. It indicates to the user that the changes made with the subdialog box cannot be reversed by clicking the Cancel button.

Requirements