undefined index id.. PHP

Question

I'm trying to delete some data from a table in a mysqli database, and I receive that error. I tried with isset, writing it directly without using a variable, nothing works. What am I doing wrong?

<?php

echo"hello";

$link = mysqli_connect("localhost", "root", "", "documents");

if($link === false){
    die("ERROR: Could not connect. " . mysqli_connect_error());
}


$ID = $_POST['id'];

$result =  mysqli_query($link, "DELETE FROM document WHERE id='$ID'");


header("Location: connect-db.php");
?>

put like $ID =isset( $_REQUEST['id']) ? $_REQUEST['id'] : 0; — Brijal Savaliya, Jun 03 '16 at 05:01
@Saty, it says: Array( ). but in the url i can see the right id "id=57". — AndrB, Jun 03 '16 at 05:02
Use`$_GET['id'];` But you are open of sql injection check http://stackoverflow.com/questions/60174/how-can-i-prevent-sql-injection-in-php?rq=1 to prevent it — Saty, Jun 03 '16 at 05:03
@BrijalSavaliya, the error dissapeared but it doesn't delete it. — AndrB, Jun 03 '16 at 05:04
coz you are getting id from url so use put like $ID =isset( $_REQUEST['id']) ? $_REQUEST['id'] : 0; OR put like $ID =isset( $_GET['id']) ? $_GET['id'] : 0;,then check it will work — Brijal Savaliya, Jun 03 '16 at 05:05
yeeey. it works. thank you so much. When I'm doing the update I receive the same error, but also for my other atributes of a document: author, title, etc. Should I write he same things there? — AndrB, Jun 03 '16 at 05:09
yes for all post and get variable we have to do same things, check "isset" — Brijal Savaliya, Jun 03 '16 at 05:21

Brijal Savaliya · Accepted Answer · 2016-06-03T05:26:00.877

1

If you are fetching id from URL then use

$ID =isset( $_REQUEST['id']) ? $_REQUEST['id'] : 0;

OR

$ID =isset( $_GET['id']) ? $_GET['id'] : 0;

If you are fetching id from POST variables then use

$ID =isset( $_POST['id']) ? $_POST['id'] : 0;

$ _REQUEST , $ _POST or $ _GET are special functions of PHP that are used to get variables from a user-filled form. While using these functions, a user may encounter an error - Notice: Undefined index. This error can be avoided with the help of PHP isset (). so you just have to check if the index exists or not before you use them.

edited Jun 03 '16 at 05:26

answered Jun 03 '16 at 05:08

Brijal Savaliya

1,101
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Please fill free to UV answer if this is helpful to you :) thanks – Brijal Savaliya Jun 03 '16 at 05:16
@AndrB , please check my updated answer :) – Brijal Savaliya Jun 03 '16 at 05:26
trying, but not enough reputation :| i'm pretty new to stackoverflow, hope UV means what I think it means, cuz if not I don't know :)) – AndrB Jun 03 '16 at 05:36

undefined index id.. PHP

1 Answers1