php使用mysqli连接数据库

$conn = mysqli_connect('localhost', 'root', '', 'addressBook') or die('Connect error!');
mysqli_set_charset($this->conn, 'utf8');       //此处不能用utf-8只能使用utf8
$sql = "insert into ".$this->tb_group." value('', '$name', '$pwd', '$numIdList')";

$result = $conn->query($sql);        //添加成功result的值为boolean值true
//$result = mysqli_query($conn, $sql);

if ($result) {
$lastid = mysqli_insert_id($conn);    //刚刚插入数据库的记录id
echo "<BR>新建通讯录成功！";
}else{
echo "<BR>新建通讯录失败！";
}