Unable to GET multiple Isset variables - php

Question

I am trying to show specific data if two variables are set in a form.
$retired = "";
$stolen = "";
if(isset($_POST['submit'])){
$retired = $_GET['showretired'];
$stolen = $_GET['showstolen'];
}
I have tried the bellow:
<?php }elseif(isset($_GET['showretired']) && (isset($_GET['showstolen'])){ ?>
Which does not work
<?php }elseif(isset($retired, $stolen)){
Which works when not set
<?php }elseif(isset($_GET['showretired'], $_GET['showstolen'])) {
This one only shows the retired part.
I am unsure of the best way to do this.
Here is the form:
<form>
<label>Show Retired Column </label><input type="checkbox" name="showretired">
<label class="space">Show Stolen Column </label><input type="checkbox" name="showstolen">
<input class="space" type="submit" name="submit" value="Refine">
</form>
This is how I am using the variable in the same file.
<?php }elseif(isset($_GET['showretired'], $_GET['showstolen'])) {
?>
<tr>
<th>Retired</th>
<th>Stolen</th>
</tr>
<?php }else{ ?>

Answer 1

<?php
if(isset($_POST['submit'])){
if(isset($_POST['showretired'])) {
$retired = $_POST['showretired'];
}
if(isset($_POST['showstolen'])) {
$stolen = $_POST['showstolen'];
}
if(isset($retired)){
echo $retired;
}
if(isset($stolen)) {
echo $stolen;
}
}
?>
<form action="" method="POST">
<label>Show Retired Column </label><input type="checkbox" name="showretired" value="The retired field">
<label class="space">Show Stolen Column </label><input type="checkbox" name="showstolen" value="The showstolen field">
<input class="space" type="submit" name="submit" value="Refine">
</form>

Answer 2

No method on the form means it will default to GET. Change the conditional and check your checkboxes.
<?php
if(isset($_GET['submit'])){
$foo = isset($_GET['foo']) ? true : false;
$bar = isset($_GET['bar']) ? true : false;
var_dump($foo);
var_dump($bar);
}
?>
<form>
<input type="checkbox" name="foo">
<input type="checkbox" name="bar">
<input type="submit" name="submit">
</form>

Answer 3

if(isset($_GET['submit'])){
if(isset($_GET['showretired']) && $_GET['showretired'] !="" && isset($_GET['showstolen']) && $_GET['showstolen'] !="" )
{
echo $retired." ".$stolen;
}
}
and form
<form>
<label>Show Retired Column </label><input type="checkbox" name="showretired" value="showretired" checked="checked">
<label class="space">Show Stolen Column </label><input type="checkbox" name="showstolen" value="showstolen" checked="checked">
<input class="space" type="submit" name="submit" value="Refine">
</form>
Hope it will help