Undefined offset PHP array - php

Question

Hello I have a code that checks for duplicates inside an xml file:
XML:
<?xml version="1.0"?>
<profielen>
<profiel>
<voornaam>a</voornaam>
<achternaam>a</achternaam>
<adres>a</adres>
<postcode>a</postcode>
<plaats>a</plaats>
<email>a</email>
</profiel>
<profiel>
<voornaam>b</voornaam>
<achternaam>b</achternaam>
<adres>b</adres>
<postcode>b</postcode>
<plaats>b</plaats>
<email>b</email>
</profiel>
<profiel>
<voornaam>c</voornaam>
<achternaam>c</achternaam>
<adres>c</adres>
<postcode>c</postcode>
<plaats>c</plaats>
<email>c</email>
</profiel>
<profiel>
<voornaam>c</voornaam>
<achternaam>c</achternaam>
<adres>c</adres>
<postcode>cL</postcode>
<plaats>c</plaats>
<email>c</email>
</profiel>
</profielen>
I can select 6 checkboxes, the more are selected the more it filters. If I select firstname, only a,b and the first person with the name c can stay and the second one will be ignored.
Now I have this code:
$xml = simplexml_load_file('/xampp/htdocs/UploadifyZWP/uploads/profiel.xml');
//Load the xml file into an array
$myArray = $_REQUEST['checkboxarray'];
//Contains the selected value (firstname = 0,lastname = 1 etc..)
if(count($myArray) <1){
//If $myArray is empty it means no checkboxes are selected and there will be no filtering
count($xml);
}else{
$fields = $myArray;
//If at least one field is selected, this code runs:
switch(count($myArray)){
case 1:
//One checkbox selected
//Array where the profiles go withouth duplicates
$profile = array();
$passed = 0;
$teller = 0;
//Loops through all the profiles in the xml array
while($passed < count($xml)){
$add = false;
//Checks for all the selected values, 1 checkbox is selected so only 0 (firstname) is selected and goes into $field
foreach($fields as $field){
if(count($profile) < 1){
//If profile is empty, add the first profile from the xml array
$add = true;
}else {
if($profile[$teller][$field] != $xml->profiel[$teller][$field])
{
$add = true;
break;
}else{
$teller++;
$passed++;
}
}
}
if($add = true){
//toevoegen
$profile[$teller] = $xml->profiel[$teller];
$teller++;
$passed++;
}
}
echo count($profile);
print_r($profile);
break;
case 2:
break;
case 3:
break;
case 4:
break;
case 5:
break;
case 6:
break;
default: echo "error";
}
}
So I put all the correct profiles in $profile array and the duplicate will be ignored. Now for testing I print the array profiles to see if it did what it should do, but the outcome is not what I was looking for. The first one (a) will be added to $profiles, the second one (b) will not, the third one (c) is added again and the fourth (duplicate(d)) is not. Now if I add 2 more profiles (e,f), e will be added and f will not. Now I have troubles installing a debugger so I don't see where it is going wrong. I also get an error that says:
Notice: Undefined offset: 1 in C:\xampp\htdocs\UploadifyZWP\ontdubbelen.php on line 37
And
Notice: Undefined offset: 3 in C:\xampp\htdocs\UploadifyZWP\ontdubbelen.php on line 37
Does anyone see where it is going wrong and why?

Answer 1

On this line if($profile[$teller][$field] != $xml->profiel[$teller][$field]) you have specified a third level of a multidimensional array but your data has only 2 levels as shown below.
SimpleXMLElement Object
(
[voornaam] => a
[achternaam] => a
[adres] => a
[postcode] => a
[plaats] => a
[email] => a
)
Try this instead
if($profile[$teller] != $xml->profiel[$teller])

Answer 2

There are a few issues with this code, but the main one is that some of the logic in it is flawed.
I'll start by saying that the if statement if($add = true) will always return true, since you are assigning rather than comparing. You need to use if ($add == true) to perform a comparison.
Other than that, it's quite hard to say exactly what you're doing wrong, because it is a general failure in logic. The main issue comes down to the fact that, on the second iteration of your while loop (starting while($passed < count($xml))), the $profile array contains one element at index 0, (meaning that count($profile) < 1 returns false, but the value of $teller is now 1, since you incremented it in the first iteration. You then try to compare the value of $profile[$teller][$field], which fails, because there is no offset of 1 in your $profile array.
Edit
To check for the existence of an index in an array, you can use isset, for example
if (isset($profile[$teller]))