Question : insert variable in php

I have a code which insert excel file data to database.

but in this code, i have to give address of excel file like this:

// initialize reader object
$excel = new Spreadsheet_Excel_Reader();

// read spreadsheet data
$excel->read('Book1.xls');

its work right but
now i want to make it form method through which i can browse and insert variable.

i have tried this:

$excelfile = $_POST['filename'];
// initialize reader object
$excel = new Spreadsheet_Excel_Reader();

// read spreadsheet data
$excel->read('$excelfile');

but it shows error  "The filename $excelfile  is not readable"

Answer : insert variable in php

Remove quotes

// read spreadsheet  data
$excel->read($excelfile);