I know you already rejected Spreadsheet::WriteExcel, but it should be noted, that module makes this easier: 
my $format = $workbook->add_format();
$format->set_align('center');
$format->set_align('vcenter');

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Also, please consider using code tags in your posts.

In reply to Re: Horizontal Alignment by SheridanCat
in thread Horizontal Alignment by jinhuang1992

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


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