Compare string from input field with value in multidimension array - php

Question

$klasseinput = strtoupper(trim($_POST["klasseliste"]));
$data = file('student.txt');
$data = array_filter($data);
foreach($data AS $row){
$student[] = explode(';', $row);
}
$antall = count($student);
for ($i = 0; $i < $antall; $i++){
if($klasseinput == $student[$i][3]){
print('<tr><td>'.$student[$i][0]."</td><td>".$student[$i][1]."</td><td>".$student[$i][2]."</td><td>".$student[$i][3]."</td></tr>");
}
}
/////////STUDENT.txt//////////
ph;petter;hanssen;IT1
gb;Geir;Bjarvin;IT2
mj;Marius;Johansen;IT3
/////////////////////////////
I am trying to compare an input form with an item in the multidimension array, but even tho the variable from the input field is exactly the same as the value in the array, it doesnt pass the if check.
$student[0][3] = IT1
$student[1][3] = IT2
$student[2][3] = IT3

Answer 1

If you have made sure there is no white space spoiling the comparison, then you might find a function like this useful to look at the strings on both sides of the comparison. You might find there are spurious characters causing trouble.
function hexdump($str)
{
for($i=0; $i<strlen($str);$i++)
{
echo "[$i] [".bin2hex($str[$i])."] [".$str[$i]."]<br />";
}
}
For instance, the string read from the file might contain CR LF characters. You could get rid of them using str_replace().

Answer 2

Thanks to Ravinder Reddy for the answer that was simple and worked for me:
" trim the value for \t\n if($klasseinput == trim($student[$i][3])){ "