How can I unset a line in PHP after pressing a submit button?

Question

I have this code now, but whenever I get to the page my entire text.txt file gets deleted. I am using sessions to get the information from a page from another php document. This is the 3rd page it directs to after information is input.

I would like choose which line to delete from the text file from an input form, but I cannot seem to get it working. Any suggestions? thanks

<?php 
$tekstFil = fopen("test.txt","r");
$t = 0;
while (!feof($tekstFil)) {

  $informasjonLinje = fgets ($tekstFil);

  echo "$t : $informasjonLinje <br/>";

  $t++;
}

fclose($tekstFil);

$fil = file("test.txt");

echo "<br/>";

echo "<form action='' type='get'>";
  echo "Velg hvilken linje med informasjon du vil slette: ";
  echo "<input type='number' name='linjeNummer' value=''>";
  echo "<input type='submit' name='slett' value='slett'>";
echo "</form>";

if(isset($_GET["slett"])) {
  echo "Du valgte å slette linje nummer: " .  $_GET["linjeNummer"];
}

$linjeNummer = $_GET["linjeNummer"];

  unset($fil[4]);

$fil = array_values($Fil);
$tekstFil = fopen("test.txt", "w");

foreach ($fil as $verdi) {
  fwrite($tekstFil, $verdi);
}
fclose($tekstFil);

`type='get'` it's not "type" it's "method". – Funk Forty Niner Nov 10 '16 at 12:58 — Funk Forty Niner, Nov 10 '16 at 12:58
and `$fil` != `$Fil`. – Funk Forty Niner Nov 10 '16 at 13:00 — Funk Forty Niner, Nov 10 '16 at 13:00
Error reporting would have been your friend. – Funk Forty Niner Nov 10 '16 at 13:06 — Funk Forty Niner, Nov 10 '16 at 13:06
@UngPeng Try the search function, `crtl + f` – Xorifelse Nov 10 '16 at 13:08 — Xorifelse, Nov 10 '16 at 13:08

score 0 · Accepted Answer · answered Nov 10 '16 at 14:40

Please try this code. There could be much simpler ways but just modified your code

<?php 

$tekstFil = fopen("test.txt","r");
$t = 0;
$buffer = array();
while (!feof($tekstFil)) {

  $informasjonLinje = fgets ($tekstFil);
  $buffer[] = $informasjonLinje;

  echo "$t : $informasjonLinje <br/>";

  $t++;
}

fclose($tekstFil);

$fil = file("test.txt");

  echo "<br/>";
  echo "<form action='' type='get'>";
  echo "Velg hvilken linje med informasjon du vil slette: ";
  echo "<input type='number' name='linjeNummer' value=''>";
  echo "<input type='submit' name='slett' value='slett'>";
  echo "</form>";

if(isset($_GET['slett'])) {
    echo "Du valgte å slette linje nummer: " .  $_GET["linjeNummer"];
    $linjeNummer = $_GET["linjeNummer"];
    //unset($fil[4]);

    //$fil = array_values($Fil);

    $tekstFil = fopen("test.txt", "w");
    unset($buffer[$linjeNummer]); 
    $buffer1 = implode("", $buffer);
    fwrite($tekstFil, $buffer1);        
    fclose($tekstFil);
}      
unset($buffer);

?>

Please try not to reload the page since you're used GET method.

Thanks, works perfectly. But I have to press the button twice for the string to be deleted. Do you know how I can fix this? — PHPnewb, Nov 10 '16 at 15:31

How can I unset a line in PHP after pressing a submit button?

1 Answers1