PHP致命错误：在第4行的C：\ Project \ Connection.php中调用未定义的函数sqlsrv_connect（）

SQL-Server connected with php 5.6 in windows server 2008.

I have installed ext folder in SqlSrv32 driver and its give extension in php.ini file. what is missing.

conncetion.php

<?php
$serverName = "WIN-FAIUOI02RDS";
$connectionInfo = array("Database" => "pi", "UID"=>"sa" , "PWD"=>"stcare@1");
$conn = sqlsrv_connect( $serverName, $connectionInfo);


?>