编写自己的CSV代码可能是浪费你的时间，只是使用一个包，如league/ CSV -它为你处理所有困难的事情，文档是很好的，它是非常稳定/可靠的:

http://csv.thephpleague.com/

你需要使用作曲家。如果你不知道什么是作曲家，我强烈建议你去看看:https://getcomposer.org/

而不是:

$query = "SELECT * FROM customers WHERE created>='{$start} 00:00:00'  AND created<='{$end} 23:59:59'   ORDER BY id";
$select_c = mysql_query($query) or die(mysql_error()); 

while ($row = mysql_fetch_array($select_c, MYSQL_ASSOC))
{
    $result.="{$row['email']},";
    $result.="\n";
    echo $result;
}

Use:

$query = "SELECT * FROM customers WHERE created>='{$start} 00:00:00'  AND created<='{$end} 23:59:59'   ORDER BY id";
$select_c = mysql_query($query) or die(mysql_error()); 

while ($row = mysql_fetch_array($select_c, MYSQL_ASSOC))
{
    echo implode(",", $row)."\n";
}

下面是@Andrew发布的php.net函数的改进版本。

function download_csv_results($results, $name = NULL)
{
    if( ! $name)
    {
        $name = md5(uniqid() . microtime(TRUE) . mt_rand()). '.csv';
    }

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

    $outstream = fopen("php://output", "wb");

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

    fclose($outstream);
}

它真的很容易使用，并且与MySQL(i)/PDO结果集一起工作。

download_csv_results($results, 'your_name_here.csv');

如果完成了页面，请记住在调用此函数后退出()。

header("Content-Type: text/csv");
header("Content-Disposition: attachment; filename=file.csv");

function outputCSV($data) {
  $output = fopen("php://output", "wb");
  foreach ($data as $row)
    fputcsv($output, $row); // here you can change delimiter/enclosure
  fclose($output);
}

outputCSV(array(
  array("name 1", "age 1", "city 1"),
  array("name 2", "age 2", "city 2"),
  array("name 3", "age 3", "city 3")
));

php: / /输出 函数

要让它以CSV格式发送，并给出文件名，请使用header():

http://us2.php.net/header

header('Content-type: text/csv');
header('Content-disposition: attachment; filename="myfile.csv"');

至于创建CSV本身，您只需要遍历结果集，格式化输出并发送它，就像处理任何其他内容一样。

最简单的方法是使用一个专门的CSV类，像这样:

$csv = new csv();
$csv->load_data(array(
    array('name'=>'John', 'age'=>35),
    array('name'=>'Adrian', 'age'=>23), 
    array('name'=>'William', 'age'=>57) 
));
$csv->send_file('age.csv');