PHP代码不工作

Question

这是我的php代码

<?php
try
{   
    $mysqlConnection = mysqli_connect('localhost', 'root', 'root');
    if($mysqlConnection)
    {
        echo "Connected"."\n";
        mysqli_select_db('test',$mysqlConnection);
        $result = mysqli_query("SELECT * from tbl_details");
        $row = mysqli_fetch_array($result);
        echo strlen($row);
    }
    else
    {
        echo "Not connected";
    }
}
catch(Exception $exp)
{
    echo $exp;
}   
?>

我已经验证了凭据并且表中也有数据，但我仍然没有得到任何记录。 任何指出为什么？

更新::

工作代码

<?php
try
{   
    $mysqlConnection = mysqli_connect('localhost', 'root', 'root','test');
    if($mysqlConnection)
    {
        echo "Connected"."\n";
        $result = $mysqlConnection->query("SELECT NAME,State FROM tbl_details");
        echo $result->num_rows."\n";
    }
    else
    {
        echo "Not connected";
    }
}
catch(Exception $exp)
{
    echo $exp;
}   
?>

Answer 1

$mysqli = new mysqli('localhost', 'my_user', 'my_password', 'my_db');
$resultaat = $mysqli->query("SELECT * FROM tabel");
while ($record = $resultaat->fetch_assoc())
{
  print_r($record);
}