<?
    // 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 );
?>

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。

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

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/

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。

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);