<?php
header('Content-Type: text/plain; charset=utf-8');

//导出CSV表格:数组转CSV
$arr = array (
  array('ab', 'cd'),
  array('"a,b"', '"c,d"'),
);
$fp = fopen('file.csv', 'w');
foreach ($arr as $row) {
  //将一行格式化为CSV并写入文件指针
  fputcsv($fp, $row);
}
fclose($fp);
unset($arr);

//导入CSV表格:CSV转数组
$fp = fopen('file.csv', 'r');
while ( ($row = fgetcsv($fp)) !== FALSE ) {
  //从文件指针中读入一行并解析CSV
  $arr[] = $row;
}
fclose($fp);
var_export($arr);

 <?php
$list = array (
  'aaa,bbb,ccc,dddd',
  '123,456,789',
  '"aaa","bbb"'
);
session_start();
$_SESSION['outputArray']=$list;
?>
<a href="test.php" target="_blank">下载csv文件</a>

<?php
session_start();
$outputArray=$_SESSION['outputArray'];
header('Content-Type: application/csv');
header('Content-Disposition: attachment;filename="sales.csv"');
$output=fopen('php://output','w') or die("can not open");
foreach ($outputArray as $line) {
  fputcsv($output, split(',', $line));
}
fclose($output) or die("can not close");
?>

<?php

$list = array (
  'aaa,bbb,ccc,dddd',
  '123,456,789',
  '"aaa","bbb"'
);

$fp = fopen('file.csv', 'w');

foreach ($list as $line) {
  fputcsv($fp, split(',', $line));
}

fclose($fp);
?>