Quick help needed

[Schlo_50]

I am trying to access a file and replace the eighth key within it with a new string. The structure of the file is:

 

stringa|stringb|stringc|stringd|stringe|stringf|stringg|old one|

 

I want to open the file, find the last key 'old one' and replace it with a new string. My code so far is:

 

	$file = file("data/customers.DAT");
foreach($file as $Key => $Val){
$Data[$Key] = explode("|", $Val);

$status = trim($Data[$Key][8]);

}

 

I think I need some sort of fopen() but im not sure how to overwrite etc..

 

Any help appreciated!

Thanks

[rhodesa]

<?php
$file = "data/customers.DAT";
$fh = fopen($file,'w');
foreach(file($file) as $Key => $Val){
  $parts = explode("|", trim($Val));
  $status = trim($parts[8]);
  $parts[8] = 'New String';
  fwrite($fh,implode("|",$parts)."\n");
}
fclose($fh);
?>

[Schlo_50]

Thank-you very much!

[Schlo_50]

Just tested that and it deleted the whole customer.DAT files contents.

 

Anything I can try to prevent?

[rhodesa]

Oops, sorry, need to do the file() before the fopen()

 

<?php
$file = "data/customers.DAT";
$lines = file($file);
$fh = fopen($file,'w');
foreach($lines as $Key => $Val){
  $parts = explode("|", trim($Val));
  $status = trim($parts[8]);
  $parts[8] = 'New String';
  fwrite($fh,implode("|",$parts)."\n");
}
fclose($fh);
?>

[wildteen88]

I'd change rhodesa code to:

$file = 'data/customers.DAT';
$new_data = '';
foreach(file($file) as $Key => $Val)
{
    $parts = explode("|", trim($Val));
    $status = trim($parts[8]);
    $parts[8] = 'New String';

    // concate each line to $new_data string.
    $new_data .= implode('|', $parts) . PHP_EOL;
}

echo '<b>Data to be written to customers.DATA:<b><pre>' . $new_data . '</pre>';

// we can then clear the contents of the customers.DAT file and rewrite the new contents:
// open the file for writing (this will clear the contents of customers.DAT)
$fh = fopen($file,'w');

// write new data to customers.DAT
fwrite($fh, $new_data);

// close file
fclose($fh);

[aschk]

You're still using the 'w' flag to write to the file. This causes an overwrite, and I believe you should be using the 'a' flag for append instead. However you'll need to seek to the previous line before appending, and this should overwrite the last line of the file, which is, i believe, what you're wanting. You want to alter the previous recored don't you, not all of them?

[rhodesa]

The 'w' does clear out the file, which is fine, you just need to make sure you read the current contents into a variable first. Opening it in append mode and trying to move the cursor around seems like an un-needed hassle. The second post I made should work.

 

Oops, sorry, need to do the file() before the fopen()

 

<?php
$file = "data/customers.DAT";
$lines = file($file);
$fh = fopen($file,'w');
foreach($lines as $Key => $Val){
  $parts = explode("|", trim($Val));
  $status = trim($parts[8]);
  $parts[8] = 'New String';
  fwrite($fh,implode("|",$parts)."\n");
}
fclose($fh);
?>

[discomatt]

A smart way to do this is to fwrite to a new temp file.

 

Ex file.txt.new

 

Once the file is written successfully, rename (and overwrite) the old file to file.txt.old and the new one to file.txt. Redundancy! If anything breaks, you have a quick reference point to recover to. Repeat

[rhodesa]

Or you can just start using MySQL 

[Schlo_50]

I am using the code you posted rhodesa, but im having trouble. The code seems to remove all lines of data apart from one.

 

I have multiple lines within the file. The code needs to search through the file for a match and then edit the last key according to the string specified. The whole code is below:

 

$file = "data/customers.DAT";
$lines = file($file);
$fh = fopen($file,'w');
foreach($lines as $Key => $Val){
  $parts = explode("|", $Val);
  $status = $parts[8];
  if ($_GET['lookup'] == $parts[0]) {

  $parts[8] = "".$_POST['status']."";
  fwrite($fh,implode("|",$parts)."\n");
}
}
fclose($fh);

 

Thanks

[rhodesa]

That is because the had the fwrite inside the IF statement. This should work for you:

 

<?php
  $file = "data/customers.DAT";
  $lines = file($file);
  $fh = fopen($file,'w');
  foreach($lines as $Key => $Val){
    $parts = explode("|", $Val);
    $status = $parts[8];
    if ($_GET['lookup'] == $parts[0]) {
      $parts[8] = $_POST['status'];
    }
    fwrite($fh,implode("|",$parts)."\n");
  }
  fclose($fh);
?>