Set cell value with condition

[TTutorials]

How to modify the cell value depend on id from another cell?
Something like if A1 = foo, and set cell value on B1 = bar

[MarkBaker]

Use a formula perhaps?

$worksheet->setCellValue('B1', '=IF(A1="bar", "foo", "not foo")');

Otherwise it's going to be a case of implementing the logic in your own code

if ($worksheet->getCell('A1)->getValue() === 'foo') {
    $worksheet->setCellValue('B1', 'bar');
}