ImageGear for C and C++ on Windows v21.0 - Updated
API Reference Guide / ISIS Component API Reference / ISIS Component Functions Reference / Choice Functions / IG_ISIS_choice_get_long
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    IG_ISIS_choice_get_long
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    Get valid byte, short, or long choice value from driver.

    Declaration:

     
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    AT_ERRCOUNT ACCUAPI IG_ISIS_choice_get_long(
            HISISDRV hDriver,
            AT_MODE nTag,
            WORD wIndex,
            LPLONG lplValue
    );
    

    Arguments:

    Name Type Description
    hDriver HISISDRV The handle to the driver.
    nTag AT_MODE The tag for which a valid byte, short, or long integer value is being requested.
    wIndex WORD An index to a particular element of the array of valid tag values.
    lplValue LPLONG A pointer to a buffer that will contain the result of IG_ISIS_choice_get_long.

    Return Value:

    Error count.

    Supported Raster Image Formats:

    This function does not process image pixels.

    Remarks:

    The IG_ISIS_choice_get_long function fills in lplValue with the value referenced by wIndex from tag nTag.

    This function must be used only for tags which have a type of IG_ISIS_TAG_TYPE_BYTE, IG_ISIS_TAG_TYPE_SHORT, or IG_ISIS_TAG_TYPE_LONG. Use the IG_ISIS_tag_get_type function to determine the type of a tag.

    The IG_ISIS_choice_get_count function can be used to determine the total number of legal values for a tag. wIndex must be at least 0 and at most the value returned by IG_ISIS_choice_get_count - 1. The constants IG_ISIS_CHOICE_LOW and IG_ISIS_CHOICE_HIGH can be used to retrieve the 0th and nth values of a list or range; however, keep in mind that a list must be sorted from low to high values for these constants to return the actual low and high values of the list. Also, IG_ISIS_CHOICE_STEP can be used if the flag IG_ISIS_CONT_RANGE is set. The value returned by IG_ISIS_choice_get_long using a wIndex value of IG_ISIS_CHOICE_STEP is the difference between any two consecutive values.

    See Also:

    IG_ISIS_choice_get_count

    IG_ISIS_tag_get_type