PHP学习：php将数组转换成csv格式文件输出的方法

<?php
$sales = array( array('east','2005-01-01','2005-02-01',12.54),
        array('west','2005-01-01','2005-02-01',546.33),
        array('south','2005-01-01','2005-02-01',93.26),
        array('north','2005-01-01','2005-02-01',945.21),
        array('All Regions','--','--',1597.34) );
$fh = fopen('file.csv','w') or die("Can't open file.csv");
foreach ($sales as $sales_line) {
  if (fputcsv($fh, $sales_line) === false) {
    die("Can't write CSV line");
  }
}
fclose($fh) or die("Can't close file.csv");
?>