I have a simple php script for throwing dices, but all dices have the same number

Question

I tried to make a dice script in php that should look like this one: http://u11626.hageveld2.nl/po/opdracht1b/index.php this is the link to mine: http://u10511.hageveld2.nl/po/opdracht1b/index.php Sorry if the answer is really obvious but i just can't figure out why the script doesn't work. btw: "knop" means "button",and the pictures that I use as dices are called dobbelsteen1, dobbelsteen2 ..... dobbelsteen 6

<?php  
session_start();
if (!isset($_SESSION["d1"]) || !isset($_SESSION["d2"]) || !isset($_SESSION["d3"])) {
    $_SESSION["d1"]=0;
    $_SESSION["d2"]=0;
    $_SESSION["d3"]=0;
}
elseif (isset($POST["knop1"])) {
    $_SESSION["d1"]=0;
}
elseif (isset($POST["knop2"])) {
    $_SESSION["d2"]=0;
}
elseif (isset($POST["knop3"])) {
    $_SESSION["d3"]=0;
}
elseif (isset($POST["knop4"])) {
    $_SESSION["d1"]=0;
    $_SESSION["d2"]=0;
    $_SESSION["d3"]=0;
}
echo "d1 =" . $_SESSION["d1"];
echo "d2 =" . $_SESSION["d2"];
echo "d3 =" . $_SESSION["d3"];
if ($_SESSION["d1"]==0) {
    $f = rand(1,6);
}

if ($_SESSION["d2"]==0) {
    $g=rand(1,6);
}

if ($_SESSION["d3"]==0) {
    $h=rand(1,6);
}
    echo $f;
for ($r=1; $r<4; $r++) {
    if (!$f==0) {
        $f = 0;
        echo "
    <div align='center'>
        <img src='dobbelsteen" . $f . ".gif'>
        <form method='post'>
        <input type='submit' name='knop1' value='Dobbelsteen gooien'>
        </form>
";
    }
    elseif (!$g==0) {
        $g = 0;
        echo "
    <div align='center'>
        <img src='dobbelsteen" . $g . ".gif'>
        <form method='post'>
        <input type='submit' name='knop2' value='Dobbelsteen gooien'>
        </form>
";
    }
    elseif (!$h==0) {
        $h = 0;
        echo "
    <div align='center'>
        <img src='dobbelsteen" . $h . ".gif'>
        <form method='post'>
        <input type='submit' name='knop3' value='Dobbelsteen gooien'>
        </form>
";
    }
}

?>

Answer 1

i have written what i consider an optimal script for this dice throwing exercise you are doing. I am giving you all the answers here but hopefully you will research my approach and learn from it.

<?php

//Start the php session
session_start();

//Initialise local dice array
//Check the session variable for already set values, if not set a random value
//Use TERNARY OPERATORS here to avoid multipl if else
$dice = array(
    0 => (!empty($_SESSION['dice'][0])) ? $_SESSION['dice'][0] : rand(1, 6),
    1 => (!empty($_SESSION['dice'][1])) ? $_SESSION['dice'][1] : rand(1, 6),
    2 => (!empty($_SESSION['dice'][2])) ? $_SESSION['dice'][2] : rand(1, 6)
);

//If form has been submitted, and our expected post var is present, check the dice we want to role exists, then role it
//$_POST['roll_dice'] holds the index of the local dice value array element we need to update
if(!empty($_POST['roll_dice']) && !empty($dice[intval($_POST['roll_dice'])])){
    $dice[intval($_POST['roll_dice'])] = rand(1, 6);
}

//Save the updated values to the session
$_SESSION['dice'] = $dice;

//Loop over the dice and output them
foreach($dice as $dice_index => $dice_val){
    echo "<div class='dice' style='height:100px;width:100px;background-color:red;text-align:center;margin-bottom:50px;padding-top:10px;'>";
    echo "<p style='style='margin-bottom:20px;'>".$dice_val."</p>";
    echo "<form method='post'>";
    echo "<input type='hidden' name='roll_dice' value='".$dice_index."' />";
    echo "<input type='submit' value='Roll Dice' />";
    echo "</form>";
    echo "</div>";
}

?>

To add a new dice simply increase the size of the $dice array. For example the next one would be:

3 => (!empty($_SESSION['dice'][3])) ? $_SESSION['dice'][3] : rand(1, 6)

and then 4, and so on.

I hope this helps.