DTWAIN_ClearPage

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The DTWAIN_ClearPage function clears the current document in the feeder and aborts the transfer for the page.

DTWAIN_BOOL DTWAIN_ClearPage ( DTWAIN_SOURCE Source )

Parameters

Source

Specifies an open TWAIN Source.

Return Values

If the function succeeds, TRUE is returned. If the function fails FALSE is returned.

Comments

The DTWAIN_ClearPage function clears the current document in the feeder and aborts the transfer for the page.

If an application decides to control the document feeding process, DTWAIN_ClearPage allows the application to terminate the acquiring of a page during acquisition of a page.

For DTWAIN_ClearPage to be successful, all of the following items must be true:

•	The Source supports a document feeder (call DTWAIN_IsFeederSupported)

•	The application has enabled the feeder (call DTWAIN_EnableFeeder)

•	The Source supports the DTWAIN_CV_CAPCLEARPAGE capability (call DTWAIN_IsCapSupported)

•	The application has turned off the auto feed (call DTWAIN_EnableAutoFeed with a FALSE argument) before the acquisition process has started.

•	The application calls DTWAIN_ClearPage during the process of acquiring.

For the last item listed above, calling DTWAIN_ClearPage can only be invoked if the application is using DTWAIN Notifications, and has intercepted the DTWAIN_TN_TRANSFERSTRIPREADY, DTWAIN_TN_TRANSFERSTRIPDONE, or DTWAIN_TN_TRANSFERDONE notifications. Only at these designated times should DTWAIN_ClearPage be called by the application.

Application control of the document feeder is best done using buffered memory transfers (DTWAIN_AcquireBuffered).

TWAIN State Transitions

None.

Prerequisite Function Call(s)

DTWAIN_SysInitialize

DTWAIN Source Selection Function

DTWAIN_EnableFeeder

DTWAIN_EnableAutoFeed (with bEnable = FALSE)

A DTWAIN Acquisition Function (preferrably DTWAIN_AcquireBuffered).