Write and Read Checkbox status to/of file with php - php

Question

I am trying to save the status of my checkbox whether it is true or false (checked/unchecked) to a file. I managed to write the checkbox value to a file but I have no idea if this is even the right way to do it and I also don't know how to load it again.
I want that my checkbox status of the last time is "remembered" by reloading the page.
Using local storage isn't a option for me sadly.....
here my code:
<form action="database.php" method="post">
<input type="hidden" name="check2" value="0" />
<input type="checkbox" name="check2" value="1" />
<input type="submit" value="senden" />
</form>
<?php
$handle = fopen("saver.json", "a");
$fh = fopen( 'saver.json', 'w' );
fclose($fh);
foreach($_POST as $value) {
fwrite ($handle, $value);
}
fclose($handle);
?>
so this first deletes the old saved value and then writes a 1 or a 0 in the file.
Am I on a good way or do I think too simple?
All help is highly apprecciated !
Thanks a lot

Answer 1

Try this solution, all checkbox status are preserved after submit, reload and even restart your browser:
<?php
// Use SESSION to store checkbox status data. SESSION seems to have a lifetime, that will erase itself if exceed.
// If you need preserve status after browser closed (), you might need to consider storing them into a file.
session_start();
$sessionTgt = NULL;
// You probaby won't need this, but if you have corrupted session
// , use "localhost://my/url/thisScript.php?reset=1" to reset/erase this session key ("saveCheckBox").
if ($_SERVER["REQUEST_METHOD"] === "GET" && isset($_GET["reset"]) && $_GET["reset"] === "1" ) {
unset($_SESSION["saveCheckBox"]);
echo("Ok, have just reset \$_SESSION[\"saveCheckBox\"]:");
exit();
}
// Reset this session key ("saveCheckBox") if it was not set.
if (!isset($_SESSION["saveCheckBox"])) {
$_SESSION["saveCheckBox"] = [
// "0" means server tell client no redirect. "1" means redirect immediately.
"ifRedirect" => "0",
// Store checkbox checked status. Example data will look like this:
// [
// "ckBox1" => "checked",
// "ckBox4" => "checked"
// ]
// , it means checkbox "ckBox1" and "ckBox4" are checked, others are not.
"checkBoxData" => [],
];
}
// Passing "reference", not value, to variable $sessionTgt.
$sessionTgt = &$_SESSION["saveCheckBox"];
// Print html form, by some condition. if some of the checkbox have "checked" status
// , then append the string "checked" inside their html <input> tag
// , so the input box will displayed as "checked".
function printFormAndCheckStatus ($checkStatus = NULL) {
echo(
'<form action="" method="post">' .
'<input type="checkbox" name="ckBox1" value="checked" ' . printCheckedMaybe("ckBox1", $checkStatus) . ' />' .
'<input type="checkbox" name="ckBox2" value="checked" ' . printCheckedMaybe("ckBox2", $checkStatus) . ' />' .
'<input type="checkbox" name="ckBox3" value="checked" ' . printCheckedMaybe("ckBox3", $checkStatus) . ' />' .
'<input type="checkbox" name="ckBox4" value="checked" ' . printCheckedMaybe("ckBox4", $checkStatus) . ' />' .
'<input type="submit" value="Submit" />' .
'</form>'
);
}
function printCheckedMaybe ($nameAttribute, $checkStatus) {
if (isset($checkStatus[$nameAttribute])) {
return "checked";
} else {
return "";
}
}
// POST "bouncing" logic. Notice the sequence is like this:
// -> Client get new page (client)
// -> Client user checked checkbox and post (client)
// -> Server save post data to SESSION (server)
// -> Server ask client for redirect (server)
// -> Client redirect immediately without doing anything (client)
// -> Server give back modified form content, that some input box has "checked" string
// appended inside the tag (client).
// The reason using double request instead of one, is to PREVENT POST DATA GET POSTED TWICE, which confuse server.
if ($_SERVER["REQUEST_METHOD"] === "POST") {
$sessionTgt["ifRedirect"] = "1";
$sessionTgt["checkBoxData"] = [];
if (isset($_POST)) {
foreach ($_POST as $name => $value) {
$sessionTgt["checkBoxData"][$name] = $value;
}
}
header("Refresh:0");
// When client get this response header pattern/content, client (browser) know he need to
// refresh the page immediately (request the same url again).
} else {
if ($sessionTgt["ifRedirect"] !== "1") {
if (isset($sessionTgt["checkBoxData"])) {
printFormAndCheckStatus($sessionTgt["checkBoxData"]);
} else {
printFormAndCheckStatus();
}
} else {
// Just after redirect.
$sessionTgt["ifRedirect"] = "0";
printFormAndCheckStatus($sessionTgt["checkBoxData"]);
}
}
Does this solve your problem? This solution save your checkbox status inside server SESSION, but SESSION seems to have a lifetime, that will erase itself if exceed. (maybe I'm wrong). If you need long term storing you can write it into a file or database.