从php中的url抓取多个变量

Question

I'm new to programming so I write logic the way I think it works for me. It may looks stupid to some of you but im in a learning process. I'm trying to use php if and elseif conditions to display information based on the url variable. It works fine when I only have one condition however I was wondering how can I make this work with multiple conditions on the same page without getting undefined index errors? Or maybe my logic is flawed?

Here what i'm trying to do:

1. Click on a link to obtain variable

2. Grab variable in the url

3. Use variable to display something specific on the dashboard

Picture of Dashboard

leftsidemenu.php

<a href='home.php?viewcompanystructure=companystructure&company=<?php echo(rand(100000000,100000000000));?>'>Company Structure</a>

   <a href='home.php?setupqualifications=qualificationssetup&company=<?php echo(rand(100000000,100000000000));?>'>
            Qualifications Setup
            </a>

  <a href='home.php?viewprojectsclients=projectsclients&company=<?php echo(rand(100000000,100000000000));?>'>
                Projects/Client Setup</a>

dashboard.php

<?php
$companytable = $_GET['viewcompanystructure'] ;
if($companytable == 'companystructure') :

    include 'tables/companytable.php';
return true;
?>

<?php
$qualificationsetuptable = $_GET['setupqualifications'] ;
elseif($qualificationsetuptable == 'qualificationssetup') :
     include 'tables/qualificationsetuptable.php'
?>

<?php
$projectclientstable = $_GET['viewprojectsclients'] ;
elseif($projectclientstable == 'projectsclients'):
     include 'tables/projectclientstable.php'
?>

<?php else: ?>
Display something else here.

<?php endif; ?>

Answer 1

If all you're doing is selecting which include to use, I'd like to suggest a alternative to your code layout.

for the given url home.php?view=companystructure ...

switch( ( isset( $_GET['view'] ) === true ) ? $_GET['view'] : null )
{
  case 'companystructure':
    include('tables/companytable.php');
    break;
  case 'setupqualifications'
    include('tables/qualificationsetuptable');
    break;
  case 'viewprojectsclients':
    include('tables/projectclientstable.php');
    break;
  default:
    include('dosomethingelse.php');
    break;
}