Replace a particular line in a text file using php? - php

Question

I have a text file that stores lastname, first name, address, state, etc as a string with a | delimiter and each record on a separate line.
I have the part where I need to store each record on a new line and its working fine; however, now I need to be able to go back and update the name or address on a particular line and I can't get it to work.
This how to replace a particular line in a text file using php? helped me here but I am not quite there yet. This overwrites the whole file and I lose the records. Any help is appreciated!
After some edit seems to be working now. I am debugging to see if any errors.
$string= implode('|',$contact);
$reading = fopen('contacts.txt', 'r');
$writing = fopen('contacts.tmp', 'w');
$replaced = false;
while (!feof($reading)) {
$line = fgets($reading);
if(stripos($line, $lname) !== FALSE) {
if(stripos($line, $fname) !== FALSE) {
$line = "$string";
$replaced = true;
}
}
fwrite($writing, "$line");
//fputs($writing, $line);
}
fclose($reading); fclose($writing);
// might as well not overwrite the file if we didn't replace anything
if ($replaced)
{
rename('contacts.tmp', 'contacts.txt');
} else {
unlink('contacts.tmp');
}

Answer 1

It seems that you have a file in csv-format. PHP can handle this with fgetcsv() http://php.net/manual/de/function.fgetcsv.php
if (($handle = fopen("contacts.txt", "r")) !== FALSE) {
$data = fgetcsv($handle, 1000, '|')
/* manipulate $data array here */
}
fclose($handle);
So you get an array that you can manipulate. After this you can save the file with fputcsv http://www.php.net/manual/de/function.fputcsv.php
$fp = fopen('contacts.tmp', 'w');
foreach ($data as $fields) {
fputcsv($fp, $fields);
}
fclose($fp);
Well, after the comment by Asad, there is another simple answer. Just open the file in Append-mode http://de3.php.net/manual/en/function.fopen.php :
$writing = fopen('contacts.tmp', 'a');