Set the current worksheet as the first worksheet

Function Prototype

setCurrentSheetIsFirst(): self

Example

$config = ['path' =>'./tests'];
$excel = new \Vtiful\Kernel\Excel($config);
$excel->fileName('hide.xlsx','sheet1') // Initialize the file and initialize the first sheet at the same time sheet1
->header(['sheet1']) // insert data in sheet1 worksheet
->addSheet('sheet2') // Add a new sheet sheet2, and set the current active sheet to sheet2
->setCurrentSheetIsFirst() // The current active sheet is sheet2, and set sheet2 as the first sheet
->output();