php text file search and delete

Question

I have a text file (in.txt) which has text on multiple lines. I need to search for a variable string and if found, delete that entire line, but keep the others. I have used the script below but it seems to get rid of all the data and write what I was searching for. Please can someone point me in the right direction? 'key' is the string for which I am searching.

$key = $_REQUEST['key'];
$fc=file("in.txt");


$f=fopen("in.txt","w");


foreach($fc as $line)
{
      if (!strstr($line,$key)) 
        fputs($f,$line); 
}
fclose($f);

score 4 · Accepted Answer · answered Mar 14 '13 at 10:03

The simplest I can come up with is

<?php

    $key = 'a';
    $filename = 'story.txt';
    $lines = file($filename); // reads a file into a array with the lines
    $output = '';

    foreach ($lines as $line) {
        if (!strstr($line, $key)) {
            $output .= $line;
        } 
    }

    // replace the contents of the file with the output
    file_put_contents($filename, $output);

score 1 · Answer 2 · answered Mar 14 '13 at 09:54

1

You have opened the file in write mode. This will delete all its data.

You should create a new file. Write data to the newer one. Delete the older one. And Rename the newer one.

OR

Open this file in read mode. Copy data of this file to a variable. Open again in write mode. And write data.

answered Mar 14 '13 at 09:54

Ashwini Agarwal

4,828
2
42
59

Ok thanks but is there not an easier way? i am not sure how to do what you suggest. – Martyn Mar 14 '13 at 09:56
When do I delete the line then? – Martyn Mar 14 '13 at 10:01
while writing to the file. – Ashwini Agarwal Mar 14 '13 at 10:02

alwaysLearn · Answer 3 · 2013-03-14T15:01:57.917

0

Its Working for me

<?php
$key = $_REQUEST['key'];
$contents = '';
$fc=file("in.txt");
 foreach($fc as $line)
  {
    if (!strstr($line,$key))
    {
       $contents .= $line; 
     }  
  }
  file_put_contents('in.txt',$contents);
 ?>

edited Mar 14 '13 at 15:01

answered Mar 14 '13 at 10:26

alwaysLearn

6,882
7
39
67

it comes up with $contents as an undefined variable. I cant work out how i sort that. Cheers. – Martyn Mar 14 '13 at 14:06
@user1592162 Hey see my edited post it should help you .. and after running this script check in.txt – alwaysLearn Mar 14 '13 at 15:02

score -1 · Answer 4 · answered Mar 14 '13 at 10:00

-1

$key = $_REQUEST['key'];
$fc=file("in.txt");


$f=fopen("in_temp.txt","w");

$temp = array();
foreach($fc as $line)
{
    if (substr($line,$key) === false) 
        fwrite($f, line);
}
fclose($f);
unlink("in.txt");
rename("in_temp.txt", "in.txt");

answered Mar 14 '13 at 10:00

KiloByte

94
3

php text file search and delete

4 Answers4