Export an Array of Arrays to Excel in php

Excel can open csv file directly ... try

$array = Array (
        0 => Array (
                0 => "How was the Food?",
                1 => 3,
                2 => 4 
        ),
        1 => Array (
                0 => "How was the first party of the semester?",
                1 => 2,
                2 => 4,
                3 => 0 
        ) 
);

header("Content-Disposition: attachment; filename=\"demo.xls\"");
header("Content-Type: application/vnd.ms-excel;");
header("Pragma: no-cache");
header("Expires: 0");
$out = fopen("php://output", 'w');
foreach ($array as $data)
{
    fputcsv($out, $data,"\t");
}
fclose($out);

The best way of exporting array to excel is here.

    $data = array(
         '0' => array('Name'=> 'Parvez', 'Status' =>'complete', 'Priority'=>'Low', 'Salary'=>'001'),
         '1' => array('Name'=> 'Alam', 'Status' =>'inprogress', 'Priority'=>'Low', 'Salary'=>'111'),
         '2' => array('Name'=> 'Sunnay', 'Status' =>'hold', 'Priority'=>'Low', 'Salary'=>'333'),
         '3' => array('Name'=> 'Amir', 'Status' =>'pending', 'Priority'=>'Low', 'Salary'=>'444'),
         '4' => array('Name'=> 'Amir1', 'Status' =>'pending', 'Priority'=>'Low', 'Salary'=>'777'),
         '5' => array('Name'=> 'Amir2', 'Status' =>'pending', 'Priority'=>'Low', 'Salary'=>'777')
        );
        $filename =  time().".xls";      
        header("Content-Type: application/vnd.ms-excel");
        header("Content-Disposition: attachment; filename=\"$filename\"");

        ExportFile($data);
        function ExportFile($records) {
            $heading = false;
                if(!empty($records))
                  foreach($records as $row) {
                    if(!$heading) {
                      // display field/column names as a first row
                      echo implode("\t", array_keys($row)) . "\n";
                      $heading = true;
                    }
                    echo implode("\t", array_values($row)) . "\n";
                }
            exit;
        }

If you really want to export array to excel, have a look at PHPReport. I have written that class to simplify exporting with phpexcel. It supports xls and xlsx.