Question

PHP PDO lab

Reorganize the code (refactor), write a separate class that implements the interface StudentInterface and use the methods in this class to show the list of students and details of a student.

- All SQL queries are moved into the methods defined in the interface and the methods return data back to the calling program.

- Use prepared statements for queries that take one or more input parameters.

interface StudentInterface {

   public function visAlle() : array;
   public function visStudent(int $id) : Student;
}

- visAlle () returns the array of references to Student objects .

- visStudent (int $ id) returns the student object with the specified id.

Student.class.php
<?php
class student {
        private $id;
        private $etternavn;
        private $fornavn;
        private $klasse;
        private $mobil;
        private $www;
        private $epost;  
        private $klassenavn;
       
        function __construct() { }
           
        function hentId() {
            return $this->id;   
        }   
        function hentNavn() {
            return $this->fornavn . " " . $this->etternavn;   
        }   
        function hentEtterNavn() {
           return $this->etternavn;
        }
        function hentForNavn() {
           return $this->fornavn;
        }
        function hentMobil() {
            return $this->mobil;
        }  
        function hentURL() {
           return $this->www;
        } 
        function hentKlasse() {
            return $this->klasse;   
        }   
          function hentEpost() {
            return $this->epost;   
        }  
        function hentKlasseNavn() {
           return $this->klassenavn;
        } 
        //Setters
        function settForNavn($fornavn) {
           $this->fornavn = $fornavn;
        }
        function settEtterNavn($etterNavn) {
            $this->etternavn = $etterNavn;
        }
        function settMobil($mobil) {
            $this->mobil = $mobil;
        }
        function settURL($www) {
            $this->www = $www;
        }
        function settKlasse($klasse) {
            $this->klasse = $klasse;
        }
        function settEpost($epost) {
            $this->epost = $epost;
        }
}
?>

StudentRegister.class.php

<?php

class StudentRegister implements StudentInterface
{
   private $db;
   
   public function __construct(PDO $db)
   {
      $this->db = $db;
   }
   
   public function visAlle(): array
   {
      $studenter= array();

        try
        {
            // implement this
        }
        catch (Exception $e) {
            print $e->getMessage() . PHP_EOL;
        }
      
      return $studenter;
    }
    
   public function visStudent(int $id) : Student
   {
        try
        {
            // implement this
        }
        catch (InvalidArgumentException $e) {
            print $e->getMessage() . PHP_EOL;
        }

   }

}

StudentInterface.class.php

<?php

interface StudentInterface {

    public function visAlle() : array;
    public function visStudent(int $id) : Student;
}

db4.php

<?php

   spl_autoload_register(function ($class_name) {
      require_once $class_name . '.class.php';
   });
    require_once 'auth_pdo.php'; 

    $studReg = new StudentRegister($db);

    if(isset($_GET['id']) && ctype_digit($_GET['id']))
    {
        $id = intval($_GET['id']);
        if($student = $studReg->visStudent($id)) {

           print("Navn: "   . $student->hentNavn() . "<br />\n");
           print("Klasse:      ". $student->hentKlasseNavn() . "<br />\n");
           print("Mobil: "   . $student->hentMobil() . "<br />\n");
           print("Epost:      ". $student->hentEpost() . "<br />\n");

        }
        else {
           // Ingen poster
           echo "Beklager, fant ingen poster!";
        }
    }
    else {
       print("Studenter:<br />");
       $studenter = $studReg->visAlle();  
       foreach ($studenter as $student )
       {
          print("<a href=" . $_SERVER['PHP_SELF'] . "?id=" . $student->hentId() . ">". $student->hentNavn() .  "</a><br/>\n");
       }
    }
     
?>

auto_pdo.php

<?php

    $host = "www.host.com";
    $dbname = "database";
    $username = "brukernavn";
    $password = "passord";

   try
   {
      $db = new PDO("mysql:host=$host;dbname=$dbname", $username, $password);
   }
   catch(PDOException $e)
   {
      //throw new Exception($e->getMessage(), $e->getCode);
      print($e->getMessage());
   }

?>

Answer 1

Answer:

Program:

Student.class.php

<?php
class student {

    private $id;
    private $etternavn;
    private $fornavn;
    private $klasse;
    private $mobil;
    private $www;
    private $epost;

    function __construct() { }

    function hentId() {
        return $this->id;
    }
    function hentNavn() {
        return $this->fornavn . " " . $this->etternavn;
    }
    function hentMobil() {
        return $this->mobil;
    }
    function hentKlasseNavn() {
        return $this->klasse;
    }
    function hentEpost() {
        return $this->epost;
    }
    function hentUrl() {
        return$this->www;
    }

    function hentEtternavn() {
        return $this->etternavn;
    }

    function hentFornavn(){
        return $this->fornavn;
    }

    public function setId($id)
    {
        $this->id = $id;
    }

    public function setEtternavn($etternavn)
    {
        $this->etternavn = $etternavn;
    }

    public function setFornavn($fornavn)
    {
        $this->fornavn = $fornavn;
    }

    public function setKlasse($klasse)
    {
        $this->klasse = $klasse;
    }

    public function setMobil($mobil)
    {
        $this->mobil = $mobil;
    }

    public function setWww($www)
    {
        $this->www = $www;
    }

    public function setEpost($epost)
    {
        $this->epost = $epost;
    }
}

StudentInterface.class.php

<?php

interface StudentInterface
{
    public function visAlle() : array;
    public function visStudent(int $id ) : student;
    public function leggTilStudent(student $student) : int;
    public function updateStudent(int $id);
    public function visKlasse() : array;
//    public function visKlasseMatte() : array;
}

StudentRegister.class.php

<?php

class StudentRegister implements StudentInterface
{

    private $db;

    public function __construct(PDO $db)
    {
        $this->db = $db;
    }

    public function visAlle(): array
    {
        $studenter= array();

        try
        {
            $result = $this->db->query("SELECT * FROM `studenter` ORDER BY `studenter`.`etternavn` ASC");
            while ($student = $result->fetchObject('Student')) {
                $studenter[] = $student;
            }
        }
        catch (Exception $e) {
            print $e->getMessage() . PHP_EOL;
        }

        return $studenter;
    }

    public function visStudent(int $id) : Student
    {
        try
        {
            $stmt = $this->db->prepare("SELECT etternavn, fornavn, mobil, www, epost FROM studenter WHERE id = :id");
            $stmt->bindParam(':id', $id, PDO::PARAM_INT);
            $stmt->execute();

            if(!$student = $stmt->fetchObject('Student')) {
                throw new InvalidArgumentException('No student with id: ' . $id);
            }
            else
                return $student;
        }
        catch (InvalidArgumentException $e) {
            print $e->getMessage() . PHP_EOL;
        }
        return $student;
    }

    public function leggTilStudent(student $student) : int
    {
        $etternavn = htmlentities($_GET['etternavn']);
        $fornavn = htmlentities($_GET['fornavn']);
        $klasse = htmlentities($_GET['klasse']);
        $mobil = htmlentities($_GET['mobil']);
        $www = htmlentities($_GET['www']);
        $epost = htmlentities($_GET['epost']);
        try {
            $stmt = $this->db->prepare("INSERT INTO `studenter` (`id`, `etternavn`, `fornavn`, `klasse`, `mobil`, `www`, `epost`, `opprettet`) VALUES (NULL, :etternavn, :fornavn, :klasse, :mobil, :www, :epost, CURRENT_TIMESTAMP)");

            $stmt->bindParam(':etternavn', $etternavn);
            $stmt->bindParam(':fornavn', $fornavn);
            $stmt->bindParam(':klasse', $klasse);
            $stmt->bindParam(':mobil', $mobil);
            $stmt->bindParam(':www', $www);
            $stmt->bindParam(':epost', $epost);
            $stmt->execute();

            $id = $this->db->lastInsertId();

        } catch (PDOException $e) {
            echo "Error: " . $e->getMessage();
        }
        return $id;
    }

    public function updateStudent(int $id)
    {
        $etternavn = htmlentities($_GET['etternavn']);
        $fornavn = htmlentities($_GET['fornavn']);
        $klasse = htmlentities($_GET['klasse']);
        $mobil = htmlentities($_GET['mobil']);
        $www = htmlentities($_GET['www']);
        $epost = htmlentities($_GET['epost']);

        try {
            $stmt = $this->db->prepare("UPDATE studenter SET fornavn= :fornavn, etternavn= :etternavn, klasse= :klasse, mobil= :mobil, www= :www, epost= :epost WHERE id = :id");
            $stmt->bindParam(':id', $id);
            $stmt->bindParam(':etternavn', $etternavn);
            $stmt->bindParam(':fornavn', $fornavn);
            $stmt->bindParam(':klasse', $klasse);
            $stmt->bindParam(':mobil', $mobil);
            $stmt->bindParam(':www', $www);
            $stmt->bindParam(':epost', $epost);
            $stmt->execute();

        }
        catch (PDOException $e){
            echo "Error: " . $e->getMessage();
        }
    }

    public function visKlasse() : array
    {
        $klassenavn = htmlentities($_GET['klasse']);
        $studenter = array();

        try {
            $stmt = $this->db->prepare("SELECT * FROM `studenter` INNER JOIN klasse on studenter.klasse = klasse.id WHERE klasse.klassenavn = :klassenavn ORDER BY `studenter`.`etternavn` ASC");
            $stmt->bindParam(':klassenavn', $klassenavn);
            $stmt->execute();
            while ($student = $stmt->fetchObject('Student')) {
                $studenter[] = $student;
            }
        }
        catch (Exception $e){
            print $e->getMessage() . PHP_EOL;
        }
        return $studenter;
    }
}

StudentRegister.php
<?php
include "../tpl/template.php";
function __autoload($class_name) {
    require_once $class_name . '.class.php';
}
require_once '../auth/auth.php';

$studReg = new StudentRegister($db);

if(isset($_GET['id']) && ctype_digit($_GET['id']))
{
    $id = intval($_GET['id']);
    if($student = $studReg->visStudent($id)) {

        print("<br/>");
        print("<a>");
        print("Navn:". htmlentities($student->hentNavn()) . "<br/>\n");
        print("Klasse: ". htmlentities($student->hentKlasseNavn()) . "<br />\n");
        print("Mobil: "   . htmlentities($student->hentMobil()) . "<br />\n");
        print("Epost: ". htmlentities($student->hentEpost()) . "<br />\n");
        print("</a>");
        print("<br/>");
    }

    else {
        echo "Beklager, fant ingen poster!";
    }
}
else{
    print("<h1>Studenter:</h1><br />");
    $studenter = $studReg->visAlle();

    foreach ($studenter as $student )
    {
        print("<a href=" . $_SERVER['PHP_SELF'] . "?id=" . $student->hentId() . ">". $student->hentNavn() . "</a><br/>\n");
    }
}
?>
    <html>
    <form action="" method="get">
        <b>
            <br>
            Velg hvilken klasse du vil se:
            <br>
        </b>
        <select name="klasse">
            <option value="">Velg tilhorighet</option>
            <option value="2sta" id="2sta">2STA</option>
            <option value="1stb" id="1stb">1STB</option>
        </select>
        <br>
        <br>
        <input type="submit" name="btn_class" value="submit">
    </form>

    </html>

<?php
if(isset($_GET['btn_class'])){
    $val = $_GET['klasse'];
    print("<br>");
    $studenter = $studReg->visKlasse();
    foreach ($studenter as $student) {
        print("<a href=" . $_SERVER['PHP_SELF'] . "?id=" . $student->hentId() . ">". $student->hentNavn() . "</a><br/>\n");
    }
}

addStudent.php

<?php
include "../tpl/template.php";
function __autoload($class_name) {
    require_once $class_name . '.class.php';
}
require_once '../auth/auth.php';

$studReg = new StudentRegister($db);
$student = new student();

if(isset($_GET['btn_add'])) {
    try {

        $nyStudent = $studReg->leggTilStudent($student);

        $student->setEtternavn('etternavn');
        $student->setFornavn('fornavn');
        $student->setKlasse('klasse');
        $student->setMobil('mobil');
        $student->setWww('www');
        $student->setEpost('epost');

        print("<br>");
        print("<a>");
        echo "Ny student lagt til!";
        print("<br>");
        print("</a>");

    } catch (PDOException $e) {
        echo "Error: " . $e->getMessage();
    }
}
?>

<html>
<form action="" method="get">

    <p>
        <label for="lastname">
            Etternavn:
            <br>
            <input id="etternavn" type="text" name="etternavn">
        </label>
    </p>

    <p>
        <label for="firstname">
            Fornavn:
            <br>
            <input id="fornavn" type="text" name="fornavn">
        </label>

    </p>

    <p>
        <label for="class">
            Klasse:
            <br>
            <input id="klasse" type="text" name="klasse">
        </label>
    </p>

    <p>
        <label for="mobile">
            Mobil:
            <br>
            <input id="mobil" type="text" name="mobil">
        </label>
    </p>

    <p>
        <label for="homepage">
            www:
            <br>
            <input id="www" type="text" name="www">
        </label>
    </p>

    <p>
        <label for="mail">
            epost:
            <br>
            <input id="epost" type="text" name="epost">
        </label>
    </p>

    <p>
        <button type="submit" name = "btn_add">Legg til student</button>
    </p>
</form>
</html>

updateStudent.php

<?php
include "../tpl/template.php";
function __autoload($class_name) {
    require_once $class_name . '.class.php';
}
require_once '../auth/auth.php';
$studReg = new StudentRegister($db);
$student = new student();

$studenter = $studReg->visAlle();

foreach ($studenter as $student )
{
    print("<a href=" . $_SERVER['PHP_SELF'] . "?id=" . $student->hentId() . ">". $student->hentNavn() . "</a><br/>\n");

    if(isset($_GET['id'])){
        $id = intval($_GET['id']);
        if($student = $studReg->visStudent($id)){
        }
    }
}

if(isset($_GET['btn_update'])) {

    try {
        $nyStudent = $studReg->updateStudent($student->hentId());

        print("<br>");
        print("<a>");
        echo "Student Oppdatert!";
        print("<br>");
        print("</a>");
    } catch (PDOException $e) {
        print("<br>");
        print("<a>");
        echo "Error: " . $e->getMessage();
        print("<br>");
        print("</a>");
    }
}

$etternavn = htmlentities($student->hentEtternavn());
$fornavn = htmlentities($student->hentFornavn());
$klasse = htmlentities($student->hentKlasseNavn());
$mobil = htmlentities($student->hentMobil());
$www = htmlentities($student->hentUrl());
$epost = htmlentities($student->hentEpost());
?>

<html>
<form action="" method="get">

    <p>
        <label for="lastname">
            Etternavn:
            <br>
            <input id="etternavn" type="text" name="etternavn" value="<?=$etternavn?>">
        </label>
    </p>

    <p>
        <label for="firstname">
            Fornavn:
            <br>
            <input id="fornavn" type="text" name="fornavn" value="<?=$fornavn?>">
        </label>

    </p>

    <p>
        <label for="class">
            Klasse:
            <br>
            <input id="klasse" type="text" name="klasse" value="<?=$klasse?>">
            <select name="klasse">
                <option value="">Velg tilhorighet</option>
                <option value="2sta" id="2sta">2STA</option>
                <option value="1stb" id="1stb">1STB</option>
            </select>
        </label>
    </p>

    <p>
        <label for="mobile">
            Mobil:
            <br>
            <input id="mobil" type="text" name="mobil" value="<?=$mobil?>">
        </label>
    </p>

    <p>
        <label for="homepage">
            www:
            <br>
            <input id="www" type="text" name="www" value="<?=$www?>">
        </label>
    </p>

    <p>
        <label for="mail">
            epost:
            <br>
            <input id="epost" type="text" name="epost" value="<?=$epost?>">
        </label>
    </p>

    <p>
        <button type="submit" name = "btn_update">Oppdater informasjon</button>
    </p>
</form>
</html>.