$worksheet->fromArray( $criteria, NULL, 'A1' ) 中的“NULL”代表什么？

Question

Can anyone please explain what "NULL" represents and why it mentions NULL and what other values or types we can mention instead of null in the following line of code

$worksheet->fromArray( $criteria, NULL, 'A1' );

Please help me to understand this line.

Answer 1

Here is the documentation: https://phpoffice.github.io/PhpSpreadsheet/classes/PhpOffice-PhpSpreadsheet-Worksheet-Worksheet.html#method_fromArray

$nullValue : mixed = null
Value in source array that stands for blank cell