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I am deleting data from a text file however whenever I delete the last item in the file a blank line is created at the bottom of the file. I need to remove this blank line however when I count the number of lines in the file it isn't recognising the blank line as a line so anything I try to delete it deletes the line above it and I am left with a blank line still. I need to remove the blank line as it causes a new iteration to be ran later on in the code.

I read into three different variables $start, $changes and $ rest. $start contains the start lines of the file (may have the blank line) and $changes contains the stuff to be deleted and then $rest contains the rest of the file if it isn't the last item. When it is the last item strlen($rest) is 0.

The basic section of the code is as follows:

$myfile = fopen("safe.txt", "w") or die("Unable to open file!");
fwrite($myfile, $start);
fwrite($myfile, $rest);

The whole code containing all the if statements is below:

$start = "";
$rest = "";
$myfile = fopen("safe.txt", "r") or die("Unable to open file!");
for ($i=0; $i<$line-1; $i++){ 
$start = $start.fgets($myfile);
}
$changes = "";
for ($i=0; $i<3; $i++){ 
$changes = $changes.fgets($myfile);
}
while(!feof($myfile)) {
$rest = $rest.fgets($myfile);
}
fclose($myfile);
$myfile = fopen("safe.txt", "w") or die("Unable to open file!");
fwrite($myfile, $start);
if ($_POST["newName"]==0 AND $_POST["delete"]==0){
fwrite($myfile, $_POST["zname"]);
fwrite($myfile, $space);
fwrite($myfile, $_POST["zlocation"]);
fwrite($myfile, $space);
fwrite($myfile, $_POST["zsize"]);
if (strlen($rest) > 0){
    fwrite($myfile, $space);
}
} elseif ($_POST["newName"]==1 AND $_POST["delete"]==0){
fwrite($myfile, $_POST["zname2"]);
fwrite($myfile, $space);
fwrite($myfile, $_POST["zlocation"]);
fwrite($myfile, $space);
fwrite($myfile, $_POST["zsize"]);
if (strlen($rest) > 0){
    fwrite($myfile, $space);
}
}
fwrite($myfile, $rest);
fclose($myfile);

The issue occurs when strlen($rest) == 0 and $_POST["delete"] == 1 This causes the file to go from: " Name Location Size Name 2 Location 2 Size 2 Name 3 Location 3 Size 3"

To: " Name Location Size Name 2 Location 2 Size 2 "

I need to remove or stop that last line being written however i have tried removing the last line and i get:

" Name Location Size Name 2 Location 2 " I have also tried $start= str_replace("\n", '', $start); and preg_replace("/(^[\r\n]|[\r\n]+)[\s\t][\r\n]+/", "\n", $start); before writing it.

littlelegs
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  • Seems like a really convoluted way of doing things ... I would simply use `file` to read the existing lines into an array, `unset` the line you want to delete from that, and write the resulting array back to the file. – CBroe Mar 07 '23 at 09:00
  • Could you please give example code? – littlelegs Mar 07 '23 at 11:34
  • https://stackoverflow.com/questions/5712878/how-to-delete-a-line-from-the-file-with-php – CBroe Mar 07 '23 at 11:42
  • This wont work for me as i don't know the contents of the line – littlelegs Mar 07 '23 at 11:54
  • You know the line _number_, so https://stackoverflow.com/a/60279855/1427878 (but with `file` instead of explode, and keep in mind that array indexes start at 0.) – CBroe Mar 07 '23 at 12:53

1 Answers1

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In case someone has a similar issue basically use trim:

$filePath = "safe.txt";
$lines = count(file($filePath));
$write = "";
$myfile = fopen("safe.txt", "r") or die("Unable to open file!");
for ($i=0; $i<$lines-4; $i++){ 
    $write = $write.fgets($myfile);
}
$val = fgets($myfile);
fclose($myfile);
$myfile = fopen("safe.txt", "w") or die("Unable to open file!");
fwrite($myfile, $write);
$val = trim($val);
fwrite($myfile, $val);

I know this probably isn't the easiest or simplest but it worked for me

littlelegs
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