Working plugin code breaks admin

Question

I would appreciate any criticism for the big chunk of code below. What I'm trying to do is query a set of custom posts and return them in a table based on custom fields. It works ... the table is being generated, the right posts are being returned, but after executing a query, all other dashboard pages are blank.

//add menu option
add_action( 'admin_menu', 'my_plugin_menu' );

function my_plugin_menu() {
    add_options_page( 'Limitless Options', 'Limitless', 'manage_options', 'limitless', 'my_plugin_options' );
}

function my_plugin_options() {
        if ( !current_user_can( 'manage_options' ) )  {
            wp_die( __( 'You do not have sufficient permissions to access this page.' ) );
        }
if( isset($_GET['set']) ) {

//variables
$checkk = array();
$meta = NULL;
$date = NULL;

    //validate
    $start = ($_GET['start'] != NULL ? $_GET['start'] : false);
    $end = ($_GET['end'] != NULL ? $_GET['end'] : false);
    $question = ($_GET['question'] != NULL ? $_GET['question'] : false);
    $answer = ($_GET['answer'] != NULL ? $_GET['answer'] : false);
    $greutate_actuala = ($_GET['greutate_actuala'] != NULL ? $_GET['greutate_actuala'] : false);
    $greutate_dorita = ($_GET['greutate_dorita'] != NULL ? $_GET['greutate_dorita'] : false);
    $check = ($_GET['check'] != NULL ? $_GET['check'] : false);

    $startEx = explode("-", $start);
    $endEx = explode("-", $end);

    if($greutate_actuala) {
      $greutate_a = array(
                 'key' => 'greutate_actuala',
                 'value' => $greutate_actuala,      
      );
    }else{
      $greutate_a = NULL;
    }

    if($greutate_dorita) {
      $greutate_d = array(
                 'key' => 'greutate_dorita',
                 'value' => $greutate_dorita,
      );
    }else{
      $greutate_d = NULL;
    }

    if($check) {
      $checkk = array(
                  'key' => 'check',
                  'value' => 1,
      );
    }

    if($question && $answer) {
      $meta = array(
                'key' => $question,
                'value' => $answer,
            );
    }
    if($question && !$answer) {
      $meta = array(
                'key' => $question,
            );
    }
    if(!$question && $answer){
        $meta = array(
                'value' => $answer,
            );
    }

    if($start && $end) {

    echo "start and end";

        $date = array(
                'after' => array(
                'year'  => $startEx[0],
                'month' => $startEx[1],
                'day'   => $startEx[2],
            ),

                'before' => array(
                'year'  => $endEx[0],
                'month' => $endEx[1],
                'day'   => $endEx[2],
            ),

            'inclusive' => true,
        );

    }
    if($start && !$end) {

    echo "start not end";

        $date = array(
            'year'  => $startEx[0],
            'month' => $startEx[1],
            'day'   => $startEx[2],
        );

    }

    $args = array(

        'post_type' => 'quiz',
        'meta_query' => array(
            $meta,
            $greutate_a,
            $greutate_d,
            $checkk,
        ),
        'date_query' => array(
            $date
        ),

    );

    $loop = new WP_Query( $args );

    echo '<table border="1" class="table">
            <tr>
              <td>Nume</td>
              <td>Email</td>
         ';

     for($i=1; $i<=10; $i++) {
        echo '<td '.(($_GET['question'] === 'question_'.$i.'') ? 'class="active"' : "").'>Question '.$i.'</td>';
     }

    echo '<td '.(($greutate_actuala) ? 'class="active"' : "").'>GA</td>
          <td '.(($greutate_dorita) ? 'class="active"' : "").'>GD</td>
          <td '.(($check) ? 'class="active"' : "").'>Check</td>
          </tr>';

    while ( $loop->have_posts() ) : $loop->the_post();
      echo '<tr>';
        echo "<td>".get_post_meta(get_the_ID(), 'name', true)."</td>";
        echo "<td>".get_post_meta(get_the_ID(), 'email', true)."</td>";

        for($i=1; $i <= 10; $i++) {
            echo "<td>".get_post_meta(get_the_ID(), 'question_'.$i.'', true)."</td>";
        }

        echo "<td>".get_post_meta(get_the_ID(), 'greutate_actuala', true)."</td>";
        echo "<td>".get_post_meta(get_the_ID(), 'greutate_dorita', true)."</td>";
        echo "<td>".get_post_meta(get_the_ID(), 'check', true)."</td>";
      echo '</tr>';

    $idArr[] = get_the_ID();

    endwhile;

    echo '</table>';

    if(isset($_POST['csv'])) {
      csvDownload($idArr);
    }

    if(isset($_POST['dl-csv'])) {
      email_csv();
    }

    echo '<form method="post" action="">
              <input type="submit" name="csv" value="csv">
          </form>
         ';

    if(isset($_POST['csv'])) {

        echo '<form method="post" action="">
              <p>CSV to: '.get_option( 'admin_email' ).' Add more: <input type="email" name="email"> ex: [email protected], [email protected]</p>
              <input type="submit" name="dl-csv" value="Send CSV">
              </form>
         ';
    }

}

Answer 1

Not sure if this is the actual answer for this but on line 252 of the pastebin link change:

 <form action="'.site_url().'/wp-admin/admin.php/options-general.php" method="get">

to

 <form action="'.admin_url('options-general.php').'" method="get">

When I submitted the form in the settings it giving me a not found error.