除了上述内容，你可能还需要补充:

header("Content-Transfer-Encoding: UTF-8");

它在处理包含多种语言的文件时非常有用，比如人名或城市。

〇简单的方法

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

$fp = fopen('data.csv', 'wb');
foreach($data as $line){
    $val = explode(",",$line);
    fputcsv($fp, $val);
}
fclose($fp);

因此$data数组的每一行都将转到新创建的CSV文件的新行。它只适用于PHP 5及以后的版本。

您可以使用fputcsv函数简单地将数据写入CSV。让我们看看下面的例子。将列表数组写入CSV文件

$list[] = array("Cars", "Planes", "Ships");
$list[] = array("Car's2", "Planes2", "Ships2");
//define headers for CSV 
header('Content-Type: text/csv; charset=utf-8');
header('Content-Disposition: attachment; filename=file_name.csv');
//write data into CSV
$fp = fopen('php://output', 'wb');
//convert data to UTF-8 
fprintf($fp, chr(0xEF).chr(0xBB).chr(0xBF));
foreach ($list as $line) {
    fputcsv($fp, $line);
}
fclose($fp);

<?
    // Connect to database
    $result = mysql_query("select id
    from tablename
    where shid=3");
    list($DBshid) = mysql_fetch_row($result);

    /***********************************
    Write date to CSV file
    ***********************************/

    $_file = 'show.csv';
    $_fp = @fopen( $_file, 'wb' );

    $result = mysql_query("select name,compname,job_title,email_add,phone,url from UserTables where id=3");

    while (list( $Username, $Useremail_add, $Userphone, $Userurl) = mysql_fetch_row($result))
    {
        $_csv_data = $Username.','.$Useremail_add.','.$Userphone.','.$Userurl . "\n";
        @fwrite( $_fp, $_csv_data);
    }
    @fclose( $_fp );
?>

下面是一个使用PDO并包含列标题的完整工作示例:

$query = $pdo->prepare('SELECT * FROM test WHERE id=?');
$query->execute(array($id));    
$results = $query->fetchAll(PDO::FETCH_ASSOC);
download_csv_results($results, 'test.csv'); 
exit();


function download_csv_results($results, $name)
{            
    header('Content-Type: text/csv');
    header('Content-Disposition: attachment; filename='. $name);
    header('Pragma: no-cache');
    header("Expires: 0");

    $outstream = fopen("php://output", "wb");    
    fputcsv($outstream, array_keys($results[0]));

    foreach($results as $result)
    {
        fputcsv($outstream, $result);
    }

    fclose($outstream);
}

在$output变量中放入CSV数据，并返回正确的报头

header("Content-type: application/download\r\n");
header("Content-disposition: filename=filename.csv\r\n\r\n");
header("Content-Transfer-Encoding: ASCII\r\n");
header("Content-length: ".strlen($output)."\r\n");
echo $output;