Hello duyet,

Just to add both methods can be used, I just test it:

my $sRGB = $parser->ColorIdxToRGB($format->{Fill}->[2]);
my $sRGB_2 = $workbook->color_idx_to_rgb($format->{Fill}->[2]);
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Also from the source code of the Spreadsheet::ParseExcel:

#---------------------------------------------------------------------
+---------
# ColorIdxToRGB (for Spreadsheet::ParseExcel)
#
# Returns for most recently opened book for compatibility, use
# Workbook::color_idx_to_rgb instead
#
#---------------------------------------------------------------------
+---------
sub ColorIdxToRGB {
    my ( $sPkg, $iIdx ) = @_;


    unless( defined $currentbook ) {
    return ( ( defined $aColor[$iIdx] ) ? $aColor[$iIdx] : $aColor[0] 
+);
    }

    return $currentbook->color_idx_to_rgb( $iIdx );
}
[download]