connect php to mysql pdo

1<?php
2$servername = "localhost";
3$username = "username";
4$password = "password";
5
6try {
7    $conn = new PDO("mysql:host=$servername;dbname=myDB", $username, $password);
8    // set the PDO error mode to exception
9    $conn->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
10    echo "Connected successfully";
11    }
12catch(PDOException $e)
13    {
14    echo "Connection failed: " . $e->getMessage();
15    }
16?>

1<?php 
2  
3	$pdo = new PDO('mysql:host=localhost;
4  				dbname=the_name_of_your_databe,
5  				'username', 
6                'password'');
7# by default your username is root 
8# if you don't have a password don't fill in it
9
10#(optional) : 
11	$pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
12	$pdo->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_OBJ);
13
14?>

1$hostName = "localhost";
2$dbName = "test";
3$userName = "test";
4$password = "test1";
5try {
6    $pdo = new PDO("mysql:host=$hostName;dbname=$dbName",$userName,$password);
7    $pdo->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
8    echo "Connected successfully"; 
9    }
10    catch(PDOException $e)
11    {
12     echo "Connection failed: " . $e->getMessage();
13    }
14