[zach014]

how can i use fwrite to write a string to the beginning on a file, instead of the end, as default.

for example, say i wanted to make a forum-type thing. I would want to make each post "appear" at the beginning, not the end.

zach

[office politics]

copy the file contents to a variable, append the variable to the new string, write the newest string.

[Vormund]

Or you can fopen with 'r+', which is read/write; it places the pointer at the start of the file.

$h = fopen("file.txt", "r+");
fwrite($h, "I'm on the first line!\n");

[zach014]

thanks csamuels, but can i make it so it simply adds onto the file instead of overwriting into the file?

[Vormund]

http://us2.php.net/fopen
If you're opening the file, just choose the appropriate mode. As I said, r+ will place the pointer at the beginning of the file, and it will not overwrite the previous.

Likewise, if you're using file_get_contents(), you would append the data, and then overwrite the old file (since all data you want is in that string).

[zach014]

sadly, that's not true. It does write into the file, replacing char for char as it goes along.

here's my page
test17.4mak.net/new

click post

[office politics]

1. get files current contents

PHP Code:

<?php
// get contents of a file into a string
$filename = "/usr/local/something.txt";
$handle = fopen($filename, "r");
$contents = fread($handle, filesize($filename));
fclose($handle);
?>

2. destroy file

3. concatenate new data with old data

PHP Code:

$new = "this is my new string";
$new = $new.$contents; 


4. write new file containing $new string

[zach014]

Just a question; how to delete and how to make a new file.

[zach014]

i'm guessing unlink is used, but somehow, it gives me errors

here's my code:

PHP Code:

<?php
$filename='index.htm';
// get contents of a file into a string
$handle = fopen($filename, "r");
$contents = fread($handle, filesize($filename));
fclose($handle);

if(unlink('index.htm'))
{ 
return true; 
}else{ 
return false; 
}  

$name = $_POST['name'];
$text = $_POST['text'];
$content = "\n<font size=4>[b]".$name."[/b]</font>
".$text."
---
";
$content = $content.$contents;

$handlet = fopen('index.htm', 'w');
fclose($handlet);

?>

[Vormund]

Originally posted by zach014
sadly, that's not true. It does write into the file, replacing char for char as it goes along.

here's my page
test17.4mak.net/new

click post

You're using the correct mode?

Anyhow, just a little shortcut, instead of fopen / etc to get the file into a string, you can use:
$contents = file_get_contents("test.txt");

And yes, as you said,
Unlike("test.txt");
should remove that file, although not needed with the right mode (dare I say).

A sample being:

PHP Code:

<?php
$filename = "test.txt";
$contents = file_get_contents($filename);
$name = $_POST['name'];
$text = $_POST['text'];
// Note: I'm thinking you want this at the top of the file, so \n should be at the end.
$content = "<font size=4>[b]".$name."[/b]</font>
".$text."
---
\n";
$contents = $content . $contents;
// This will take care of "removing" the file for the new contents.
// w - Open for writing only; place the file pointer at the beginning of the file and truncate
// the file to zero length. If the file does not exist, attempt to create it.
$h = fopen($filename, 'w');
fwrite($h, $contents);
fclose($h);
?>

Or just appending the file:

PHP Code:

<?php
$filename= "test.txt";
$name = $_POST['name'];
$text = $_POST['text'];
// Note that the \n is not used here.
$content = "<font size=4>[b]".$name."[/b]</font>
".$text."
---
";
if (file_exists($filename))
{ // The file exists, so put the pointer at the beginning and add the content.
  $h = fopen($filename, 'r+');
  fwrite($h, $content."\n");
}
else
{ // The file does not exist, so create it...and add the contents without the newline character.
  $h = fopen($filename, 'w');
  fwrite($h, $content);
}
// Close our handle.
fclose($h);
?>