error Notice: Undefined index

[langy]

I have recently chosen a placement for workexperience in year ten and as part of preporation they have asked me to learn PHP. I had started learning before and had created a few documents including one where you can sign in to get some information. I created and tested this on a WOS server and it was working fine, however that server stoped working so i dowlanded WAMP, i tested the file i made before and now get an error i didnt get before:

Notice: Undefined index: Ipassword in C:\wamp\www\dev\Lib\dkplib.php on line 13

On line 13 and the surrounding lines i have this script:

 $Ipassword = $_REQUEST["Ipassword"];
 $Iusername = $_REQUEST["Iusername"];

i am also getting the same error for line 14.

when i sign in the information it did show is instead replaced by:

Notice: Undefined index: in C:\wamp\www\dev\Lib\dkplib.php on line 87

on line 87 and surrounding lines if have the followng script:

function get_data() 
{
global $data ,$user;
echo "<div id=\"data\">";
echo "<u><h1>Data</h1></u>";
echo "<b>Username: </b>" .$user;
echo "<br><b>DKP: </b>" .$data["$user"]["dkp"];
echo "<br><b>Rank: </b>" .$data["$user"]["rank"];
echo "<br><b>Other data: </b>" .$data["$user"]["other_data"];
echo "</div>";
}

I have used google to search the error message but the only result i can find is disabling the error reports but i dont want ot hide it i want to solve it, because i am not getting the information instead this error report.

Will disabling the error report work and if so, how od i do that and if not what should i do?

[NogDog]

The problem is that those $REQUEST array elements are not set at the time you are trying to access them. Whether that is a bug or a normal occurrence is a separate issue, depending on your application design. To avoid the notice, you can first test to see if they are set:

$Ipassword = isset($_REQUEST["Ipassword"]) ? $_REQUEST["Ipassword"] : '';
$Iusername = isset($_REQUEST["Iusername"]) ? $_REQUEST["Iusername"] : '';

As far as the error in your function, I would guess that either $data or $user is not set or has an empty value. This is just one of the reasons that using "global" can cause problems and is generally avoided. It would probably be better to pass them as function parameters. Either way, you can still do some defensive programming and check to see if the array element in question is set before trying to do anything with it.

if(isset($data[$user]))
{
   // go ahead and do stuff with it
}
else
{
   // log error and return false, or raise fatal error, or throw exception
}