If url variable is empty redirect to home page

问题

I am not able to get this to work correctly!!

I have a view.php page that uses a variable of 'ID' to retrieve db info.

So my url is like this:

/view.php?id=23 

I am trying to get it to "redirect" the user to the home page if they erase the "23" part of the url.. ?

so when you visit

/view.php?id=

It should :

if(isset($_GET['id']) == "") 
{ 
header('Location: /');
exit; }

Works if I visit

/view.php

回答1:

Try using empty():

if(empty($_GET['id'])) 
{ 
  header('Location: /');
  exit; 
}

回答2:

Another way:

if(strlen($_GET['id'])>0) { 
 header('Location: /');
 exit; 
}

来源：https://stackoverflow.com/questions/13848629/if-url-variable-is-empty-redirect-to-home-page