Phpexcel how to format cells as ZIP codes

Phpexcel how to format cells as postal code
When you export a table using Phpexcel, there is a column zip code, and some zip codes start with 0 and are hidden in the table.
So I set the cell format to a string, the content is displayed correctly, but there is a

Error tip of the small triangle ( test there pass though )

There is a zip code in the cell format of Word, this option


But in the Phpexcel document did not find the ZIP code in this format, we have encountered this situation?
------Solution--------------------
Cases

$sheet->getstyle (' D7 ')
            ->getnumberformat ()
            ->setformatcode (' 000000 ');

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