OOP面向对象-用mysqli类连接数据库

//连接数据库
$mysqli = new mysqli('localhost','root','root','user');
//判断是否连接成功  //>0
if($mysqli->error>0){
    echo $mysqli->error;
    die;
}
//print_r($mysqli);  ///object

//设置字符集
$mysqli->set_charset('utf8');

//设置sql语句
$sql = "select * from info";
//执行
$result = $mysqli->query($sql);//返回object
//print_r($result);
//处理结果集
if($result && $result->num_rows>0){
    $list = $result->fetch_all(MYSQLI_ASSOC);
}
//echo "
";
//print_r($list);//返回二维数组
//关闭对象
$mysqli->close();