PHP If statement not redirecting on blank string

Question

I have some code that is entering values into a database. I have an IF statement at the start to check if the string $jobno is empty and if it is, it redirects back to the form. But its not redirecting just runs the code successfully.

if ($jobno=='') {
        header( 'Location: add_job.php?error=1');
    }

What am I doing wrong?!

 <?php
$status=$_POST["status"];
$jobno=$_POST["jobno"];
$number=$_POST["number"];
$street=$_POST["street"];
$suburb=$_POST["suburb"];
$city=$_POST["city"];
$first_name=$_POST["first_name"];
$first_name = ucfirst($first_name);
$last_name=$_POST["last_name"];
$last_name = ucfirst($last_name);
$landline=$_POST["landline"];
$mobile=$_POST["mobile"];
$fax=$_POST["fax"];
$email=$_POST["email"];

if ($jobno=='') {
    header( 'Location: add_job.php?error=1');
}

$con=mysqli_connect("server","user","pass","database");
// Check connection
if (mysqli_connect_errno()) {
  echo "Failed to connect to database: " . mysqli_connect_error();
}

mysqli_query($con,"INSERT INTO jobs (status, jobno, number, street, suburb, city, first_name, last_name, landline, mobile, fax, email)
VALUES ('$status', '$jobno', '$number', '$street', '$suburb', '$city', '$first_name', '$last_name', '$landline', '$mobile', '$fax', '$email')");

mysqli_close($con);

header( 'Location: photo_upload.php?new_job_success=y&jobno=' . $jobno ) ;

?>

Then It should be other than empty string `''`. Instead do strict type comparison `===` — Rahil Wazir, Aug 15 '14 at 13:38
I hope this isn't your production script!! as the severe lack of sanitisation is terrifying. — RaggaMuffin-420, Aug 15 '14 at 13:38
What do you mean by var_dump($jobno); DoXicK. Sorry bit of a newbie — georgewoofbates, Aug 15 '14 at 13:39
Try if (empty($jobno)) {header ('Location: add_job.php?error=1')} — AllisonC, Aug 15 '14 at 13:40
Its not the finished script RaggaMuffin-420 but what do you mean by sanitisation? Any help would be greatly appreciated — georgewoofbates, Aug 15 '14 at 13:40
@georgewoofbates please tell me your not developing this for consumer use, and its just a school project or something! please google `data sanitisation php` or something. — RaggaMuffin-420, Aug 15 '14 at 13:44
Use [error reporting](http://php.net/manual/en/function.error-reporting.php) and I'm next to convinced that you'll get an error "headers already sent...." - Error reporting meaning, `error_reporting(E_ALL); ini_set('display_errors', 1);` placed right after your opening ` — Funk Forty Niner, Aug 15 '14 at 13:46
possible duplicate of [How to fix "Headers already sent" error in PHP](http://stackoverflow.com/questions/8028957/how-to-fix-headers-already-sent-error-in-php) — Funk Forty Niner, Aug 15 '14 at 14:10

score 2 · Answer 1 · answered Aug 15 '14 at 13:42

2

 <?php
^---this space

is OUTSIDE of your code, so it's output, which makes

header( 'Location: add_job.php?error=1');

cause a "headers already sent" error.

You are also wide open and begging for an SQL injection attack

answered Aug 15 '14 at 13:42

Marc B

356,200
43
426
500

Sorry what do you mean by this space is outside of your code? I'm confused – georgewoofbates Aug 15 '14 at 13:49
Basic PHP: Anything not within `` code blocks is simply output. **ANY** output triggers automatic sending of the response headers to the client. Your `Location:` is such a header, and can't be sent after output has started, because it'd simply become part of the response BODY. – Marc B Aug 15 '14 at 13:51
So I need to put the Header: Location into the tag? – georgewoofbates Aug 15 '14 at 13:54
No. php header() calls having **NOTHING** to do with `` blocks. header() sends an HTTP header. You should go read about the HTTP protocol's request/response formats. – Marc B Aug 15 '14 at 13:56

score 1 · Accepted Answer · edited Aug 15 '14 at 13:48

1

It could be 2 things

$jobno is not ''
since you aren't returning after your redirect, and you are doing a second redirect a bit later, your header would look like:
- Location: add_job.php?error=1
- Location: photo_upload.php?new_job_success=y&jobno=

put an else clause in your code:

<?php
...
if ($jobno=='') {
    header( 'Location: add_job.php?error=1');
}
else {
  $con=mysqli_connect("server","user","pass","database");
  // Check connection
  if (mysqli_connect_errno()) {
    echo "Failed to connect to database: " . mysqli_connect_error();
  }
  else
  {
    mysqli_query($con,"INSERT INTO jobs (status, jobno, number, street, suburb, city,first_name, last_name, landline, mobile, fax, email) VALUES ('$status', '$jobno', '$number', '$street', '$suburb', '$city', '$first_name', '$last_name', '$landline', '$mobile', '$fax', '$email')");

    mysqli_close($con);

    header( 'Location: photo_upload.php?new_job_success=y&jobno=' . $jobno ) ;
  }
}

?>

edited Aug 15 '14 at 13:48

RaggaMuffin-420

1,762
1
10
14

answered Aug 15 '14 at 13:41

DoXicK

4,784
24
22

definitely advise the `if...else...` as i'm pretty sure the script will run even if you define the header, as the `header` doesn't kill the script. +1 – RaggaMuffin-420 Aug 15 '14 at 13:42
@RaggaMuffin-420 i know that is the problem indeed :-) but it never helps to put them in the right direction to let them properly check a value first. Debugging is such helpful skill! – DoXicK Aug 15 '14 at 13:44
did you change your script? as I'd use an else on the `if($jobno=='') { ... } else { ... }` – RaggaMuffin-420 Aug 15 '14 at 13:45
Oh right that's a good point using the else. Thanks I'll try that! – georgewoofbates Aug 15 '14 at 13:51
Is there any other way I can redirect without having to use the headers if this is going to be an ongoing problem? – georgewoofbates Aug 15 '14 at 14:23
you could go for a meta-redirect in the header and for a javavascript redirect (location.href = blabla)... – DoXicK Aug 15 '14 at 14:27

score 0 · Answer 3 · answered Aug 15 '14 at 13:56

There is an space in the starting which is causing this error. You can't echo any output before sending the headers not even a single space. This small space is causing the header already sent error.You should remove the space on the starting of the php file. Your code should look like this

<?php
$status=$_POST["status"];

I hope this helps you

score -1 · Answer 4 · answered Aug 15 '14 at 13:40

-1

I think you must to use isset function. http://php.net/manual/en/function.isset.php

answered Aug 15 '14 at 13:40

al_kash

87
4

score -1 · Answer 5 · answered Aug 15 '14 at 13:40

-1

try using this code:

if (!isset($_POST["jobno"])) {
    header( 'Location: add_job.php?error=1');
}

answered Aug 15 '14 at 13:40

koosie

54
4

makes no difference, if its not set, then PHP will throw a warning and set the variable to `null` and `'' == null` is true. – RaggaMuffin-420 Aug 15 '14 at 13:41
it still just goes through fine! – georgewoofbates Aug 15 '14 at 13:42

PHP If statement not redirecting on blank string

5 Answers5