An Open or Save As dialog box sends the SHAREVISTRING registered message to your hook procedure if a sharing violation occurs for the selected file when the user clicks the OK button.
For Explorer-style Open and Save As dialog boxes, this message has been superseded by the CDN_SHAREVIOLATION notification message.
MessageID = RegisterWindowMessage(SHAREVISTRING);
wParam = 0;
lpofn = (LPOPENFILENAME) lParam;
The hook procedure must return one of the following values to indicate how the dialog box should handle the sharing violation:
Return value |
Description |
OFN_SHAREFALLTHROUGH |
Accept the filename |
OFN_SHARENOWARN |
Reject the filename but do not warn the user. The application is responsible for displaying a warning message. |
OFN_SHAREWARN |
Rejects the filename and displays a warning message (the same result as if there were no hook procedure). |
The hook procedure must specify the SHAREVISTRING constant in a call to the RegisterWindowMessage function to get the identifier for the message sent by the dialog box.
The dialog box sends the SHAREVISTRING registered message only if you did not specify the OFN_SHAREAWARE flag in the Flags member of the OPENFILENAME structure when you created the dialog.
If the hook procedure returns an undefined value, the dialog box responds as if OFN_SHAREWARN was returned.