PHP7 配置mySQL 失败！求解救。

Question

RT，我想要配置PHP环境。
结果配置完成，提示 “could not find driver”！
windows10 x64环境。
PHP版本为：

                php-7.1.3-nts-Win32-VC14-x64

按照一般的配置流程，我先修改了php.ini-development和php.ini-production两个文件（两个文件内容长得一样，我都改了）：

        extension_dir = "D:\php-7.1.3-nts-Win32-VC14-x64\ext"

 ;
;extension=php_bz2.dll
;extension=php_curl.dll
;extension=php_fileinfo.dll
;extension=php_ftp.dll
;extension=php_gd2.dll
;extension=php_gettext.dll
;extension=php_gmp.dll
;extension=php_intl.dll
;extension=php_imap.dll
;extension=php_interbase.dll
;extension=php_ldap.dll
;extension=php_mbstring.dll
;extension=php_exif.dll      ; Must be after mbstring as it depends on it
;extension=php_mysqli.dll
;extension=php_oci8_12c.dll  ; Use with Oracle Database 12c Instant Client
;extension=php_openssl.dll
extension=php_pdo_firebird.dll
extension=php_pdo_mysql.dll
extension=php_pdo_oci.dll
extension=php_pdo_odbc.dll
extension=php_pdo_pgsql.dll
extension=php_pdo_sqlite.dll
;extension=php_pgsql.dll
;extension=php_shmop.dll
extension=php_pdo_sqlsrv_7_nts_x64.dll
extension=php_sqlsrv_7_nts_x64.dll

; The MIBS data available in the PHP distribution must be installed.
; See http://www.php.net/manual/en/snmp.installation.php
;extension=php_snmp.dll

;extension=php_soap.dll
extension=php_sockets.dll
;extension=php_sqlite3.dll
;extension=php_tidy.dll
;extension=php_xmlrpc.dll
;extension=php_xsl.dll

然后，我加入了系统环境变量：

     D:\php-7.1.3-nts-Win32-VC14-x64;

但是并没有什么乱用：

 测试mysql数据库连接。Error!: could not find driver

 <?php 
    echo "测试mysql数据库连接。";
    phpinfo();
    class test
    {
        public function conntest()
        {
            $connInfo = array(
                $dbhost => 'localhost:3306',
                $dbname => 'mydb',
                $dbuser => 'Even',
                $dbpwd  => '446639'
            );
            try{
                $pdo = new PDO(
                    'mysql:host = localhost,dbname = mydb',
                    $connInfo[$dbuser],
                    $connInfo[$dbpwd]
                );
            }
            catch(PDOException $e)
            {
                print "Error!: " . $e->getMessage() . "<br/>";
            }
            if(!$conn)
            {
                die();
            }
            else
            {
                echo "连接成功";    
            }

        }
    }
    $obj = new test();
    $obj->conntest();
?>

phpinfo（）中，没有显示PDO驱动信息：(No Value)

PDO drivers  no value  

以上。
求助……在线等。

Answer 1

版本是否匹配，驱动是否完全呢？