Get the total number of legal values for a tag.

Declaration:

AT_ERRCOUNT ACCUAPI IG_ISIS_choice_get_count(
        HISISDRV hDriver,
        AT_MODE nTag,
        LPWORD lpwCount
);

Arguments:

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:

This function does not process image pixels.

Example:

See IG_ISIS_choice_get_ascii example.

Remarks:

The IG_ISIS_choice_get_count function retrieves the total number of legal values from a specified tag.

The IG_ISIS_choice_get_countfunction can be used to determine the valid range of the wIndex parameter to use in other IG_ISIS_choice_get... functions. The range is zero to (*lpwCount - 1).

If the tag is defined, IG_ISIS_choice_get_count always returns IGE_SUCCESS. The value returned in lpwCount is valid, and its value depends on the type of choice node for the specified tag:

• If a choice node is defined for the tag, lpwCount specifies the available number of values in the current node.
• If the choice node is a range node, the value returned in lpwCount specifies the number of values computed by ((MAX - MIN) / STEP).
• If no choice node is defined for the tag, lpwCount contains the value 1.

IG_ISIS_choice_get_count returns the correct value even if the choices for a tag are represented as a range (low, high, step).

See Also:

IG_ISIS_choice_get_ascii

IG_ISIS_choice_get_long

IG_ISIS_choice_get_rational

IG_ISIS_tag_get_type