This code snippet primarily deals with iterating through all worksheets...

This code snippet primarily deals with iterating through all worksheets in a spreadsheet and yielding data row-by-row from each worksheet. Here’s a breakdown of what it does:

1. Iterate Through Worksheets:

   • The foreach loop fetches each worksheet in a spreadsheet using $this->getSheet()->getWorksheetIterator().
   • Each worksheet is processed in turn.

2. Yield Title and Process Rows:

   • For each worksheet, the code uses the yield keyword to return two pieces of data:
     • The title of the current worksheet ($worksheet->getTitle()).
     • A generator function (an anonymous static function) that processes the rows in that worksheet.

3. Anonymous Function Execution:

   • The static anonymous function takes the current worksheet as an argument.
   • Inside this function:
     • $maxRow is retrieved using $worksheet->getHighestRow(), which represents the number of rows in the worksheet.
     • The column headers are retrieved by calling a self::getFirstRow($worksheet) method, which likely gets the first row of the worksheet as column names.

4. Iterate Over Rows:

   • A loop runs through each row in the worksheet, starting at row 2 (to skip the headers).
   • A foreach loop iterates through the columns ($cols) of the row, mapping the column names to their corresponding values (retrieved using $worksheet->getCell([$i, $r])->getValue()).
   • The row data is constructed as an associative array ($row) with the column names as keys and corresponding cell values as values, and then yielded.

5. Yielded Row-by-Row Data:

   • For each worksheet, the function constructs and yields rows of data until all rows in the worksheet have been processed.

Summary:

This code is essentially used to process and extract data from a spreadsheet file (likely using a library such as PhpSpreadsheet). Here's what it does:

• Iterates through each worksheet in a spreadsheet.
• For each worksheet:
  • Yields the worksheet's title.
  • Yields a generator that outputs all rows of data (as associative arrays) from that worksheet, with column headers as keys and cell values as values.

This allows the consumer of this code to read and access spreadsheet data in a memory-efficient manner using generators.