My array values keep dissapearing and refreshing in php? - php

Question

I want to be able to add new values to the array called playlist using functions (is mandatory). But everytime I input another value it replaces the old one instead of just adding on the end of the array. What is wrong?
<?php
$playlist = array("Be more.mp3", "Drift Away.mp3", "Panda Sneeze.mp3");
function add_songs_playlist() {
global $playlist;
?>
<form method = "post">
<input type = "text" name = "name1"/>
<input type = "submit" name = "submit1"/>
</form>
<?php
if (isset($_POST['submit1'])) {
$newsong = $_POST['name1'];
array_push($playlist, $newsong);
}
}
add_songs_playlist();
foreach ($playlist as $value) {
echo $value."<br>";
}

Answer 1

PHP values aren't saved between requests. Every time this page loads, $playlist starts out with those same three values you assign.
If you want to keep data around longer, you'll need to save it somewhere—a cookie, a file, the session, a database, etc.
Alternatively, you could store the values in the HTML itself, by printing an <input type="hidden"> for each song in the playlist. Then when the user enters a new song, you have the new song plus the full list of all the old ones.

Answer 2

Just write the playlist to a file
<?php
if (isset($_POST['submit1'])) {
$song = "\n".$_POST['name1'];
$file = fopen("songs.txt", 'a');
fwrite($file, $song);
fclose($file);
}
$file = file("songs.txt");
foreach ($file as $song) {
echo $song . "</br>";
}
?>
<form method = "post">
<input type = "text" name = "name1"/>
<input type = "submit" name = "submit1"/>
</form>

Answer 3

There is a general mistake you make:
you have to understand that each time you transmit a value the way you do, you php script is started again. It restarts without anything left from the last time.
To be able to take over values the way you want to you have to store those values in a persistant manner after having pushed them to the array. During the next run you first have to read the existing values from that persistant storage, fill the array and only then you can add another value on top of that array. This is a general principle, the basic way this kind of framework works.
Typically a database is used as persistant storage, but also files might be interresting, depending on how many request and how much data you plan to process.

Answer 4

Here is an small mod of your code. I removed the function and stored your array within the form itself.
This one will work without storing any information on the server, bet I don't think it wil be very usable. You should store your content like suggested by #Anonymous in previous reply.
Working code:
<?php
// First check if I get a POST request with list of songs
if (isset($_POST['playlist'])) {
$playlist = $_POST['playlist'];
} else { // Else set my default list
$playlist = array("Be more.mp3", "Drift Away.mp3", "Panda Sneeze.mp3");
}
// You need to get the added son BEFORE you generate the FORM,
// so it can be a part of the form
if (isset($_POST['name1'])) {
$playlist[] = $_POST['name1'];
}
?>
<form method = "post">
<?php
// This loop stores your songs as hidden values within the form,
// so you will get them with your next post
foreach($playlist as $song) {
?>
<input type = "hidden" name = "playlist[]" value = "<?php echo $song?>">
<?php
}
?>
<input type = "text" name = "name1"/>
<input type = "submit" name = "submit1"/>
</form>
<?php
foreach ($playlist as $value) {
echo $value."<br>";
}

Answer 5

An example specific to your repost code would be:
if (isset($_POST['submit1'])) {
$newsong = $_POST['name1'];
$playlist[] = $newsong;
}
Also an error may be the fact your form is within a function... why not just do this
<?php
$playlist = array("Be more.mp3", "Drift Away.mp3", "Panda Sneeze.mp3");
?>
<form method = "post">
<input type = "text" name = "name1"/>
<input type = "submit" name = "submit1"/>
</form>
<?php
if (isset($_POST['submit1'])) {
$newsong = $_POST['name1'];
$playlist[] = $newsong;
}
foreach ($playlist as $value) {
echo $value."<br>";
}
?>
I am not sure if you care if the page refreshes. But if you are fine with a page refresh this should work. If you do not want a refresh you can either save your variables in javascript and do your work in that and use the form button onClick as a function call. Or if you want to work your variables in PHP in-order to reset your php variable without refreshing you will need to make an AJAX call to call back JSON to update your PHP variable.