Using the bootstrap form with $_GET method on same page - php

Question

Im having trouble getting my form code to work, i want it to when they submit it to change the current page url, ex: weaw.com?id=Summitedtext and i am echoing it out from php.
$cmd = 'htmlspecialchars($_SERVER["PHP_SELF"])'
echo '<form id="idform" action="' . $cmd . '" method="GET">';
echo '<label><center>To search an inventory please put the users Profile URL in the input box below.</center></label>';
echo '<div class="input-group">';
echo '<span class="input-group-addon" id="basic-addon1"><span class="glyphicon glyphicon-user" aria-hidden="true"></span></span>';
echo '<input type="text" class="form-control" placeholder="Profile URL" aria-describedby="basic-addon1">';
echo '<span class="input-group-btn">';
echo '<button class="btn btn-default" type="submit" name="submit" value="Submit">Go!</button>';
echo '</span>';
echo '</form>';
echo '</div>';

Answer 1

Totally disagree with echoing form but change your code to this and add your ingredients such class and so on:
<?PHP
if(isset($_GET['url'])
$cmd = htmlspecialchars($_GET['url']);
else
$cmd = htmlspecialchars($_SERVER["PHP_SELF"]);
?>
<form id="idform" action="<?PHP echo $cmd; ?>" method="GET">
<input type="text" name="url">
<input class="btn btn-default" type="submit" name="submit" value="Go!" />
</form>