ImageGear for C and C++ on Windows v21.0 - Updated
API Reference Guide / Core Component API Reference / Core Component Functions Reference / Multi Page Image Functions / IG_mpi_CB_get
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    IG_mpi_CB_get
    In This Topic

    This function returns information about the associated private data pointer and update function using the dwCBID identifier.

    Declaration:

     
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    AT_ERRCOUNT ACCUAPI IG_mpi_CB_get( 
            [IN] HMIGEAR hMIGear, 
            [IN] DWORD dwCBID, 
            [OUT] LPVOID FAR* lplpPrivate,
            [OUT] LPFNIG_MPCB_UPDATE FAR* lplpfnUpdate
    );
    

    Arguments:

    Name Type Description
    hMIGear HMIGEAR The handle of the allocated multi-page image.
    dwCBID DWORD A unique identifier of the private data and function.
    lplpPrivate LPVOID FAR* A pointer indicating where to receive the private data.
    lplpfnUpdate LPFNIG_MPCB_UPDATE FAR* A pointer indicating where to receive the update function.

    Return Value:

    Returns the number of ImageGear errors that occurred during this function call. If there are no errors, the return value is IGE_SUCCESS.

    Supported Raster Image Formats:

    All pixel formats supported by ImageGear for C and C++.

    Sample:

    None

    Example:

     
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    HMIGEAR          hMIGear;    /* handle to multi-page image */
    AT_ERRCOUNT nErrCount = IGE_SUCCESS; /* will hold returned error count */
    LPVOID lpData;
    LPFNIG_MPCB_UPDATE        lpUpdateFunc;
    DWORD dwCBID;
     ...
    nErrCount = IG_mpi_CB_set( hMIGear, (LPVOID)hMIGear, _MPWndUpdate, &dwCBID );
     ...
    nErrCount = IG_mpi_CB_get( hMIGear, dwCBID, &lpData, &lpUpdateFunc );
     ...
    VOID  ACCUAPI  _MPWndUpdate(
       DWORD          dwCBID,
       LPVOID         lpPrivate,     /* Private data passed in */
       AT_MODE        nMode,
       UINT           nPage,
       UINT           nCount
    )
    {
       switch( nMode )
       {
       case  IG_MPCBMODE_MPI_DELETE:
             ...
          break;
       case  IG_MPCBMODE_MPI_ASSOCIATED:
             ...
          break;
       case  IG_MPCBMODE_MPI_CLOSE:
             ...
          break;
             ...
       }
    }
    

    Remarks:

    See the IG_mpi_CB_set() documentation for a description of how notification works with multi-page images.

    If there is no association with an external file, then NULL values are assigned to both pointers.