Deleting, clearing, and creating files

[stophon4]

Is it possible to delete, clear, and create files with php?

[Len Whistler]

Yes..you can also create folders.

[CraigC]

http://php.net/filesystem is the filesystem function reference, though you'll probably be only interested in fopen (http://ca3.php.net/manual/en/function.fopen.php) for now, as it has a list of the basic functions at the bottom (before the comments)

[stophon4]

WOW! Php is very powerful. That is amazing :eek:

New question:

Is it possible to tell php to delete something in the middle of a file, or start the cursor there?

[firepages]

see fseek() (http://www.php.net/fseek)

[stophon4]

Sorry, I didn't see that.

I took one of there example scripts and get errors
script:

<?php

$fp = fopen('test_file.txt');

// read some data
$data = fgets($fp, 4096);

// move back to the beginning of the file
// same as rewind($fp);
fseek($fp, 0);

?>


errors:

Warning: fopen() expects at least 2 parameters, 1 given in /data/hosted/stophon4/ftell.php on line 3

Warning: fgets(): supplied argument is not a valid stream resource in /data/hosted/stophon4/ftell.php on line 6

Warning: fseek(): supplied argument is not a valid stream resource in /data/hosted/stophon4/ftell.php on line 10


Is it just my servers problem or am I not understanding this and missing something?

EDIT: I got a better idea. What code would I need to delete a line or insert a line somewhere (and type on that linee)?

I forgot to say earlier: All help is greatly appreicated :p

[firepages]

you still need to open with a mode , here r+ if you want to seek and write


<?
$fp = fopen( 'test_file.txt' , 'r+' ) ;
?>

[stophon4]

I don't really get that, what code would I need to delete line 3 of a document ?

[firepages]

just a line ? easist is along the lines of , note that '2' here is 'line 3' as the $file array counts from 0;


<?
$filename = 'text.txt' ;
/*read file into memory as an array*/
$array= file( $filename ) ;

/*clear the contents of line 3*/
unset($array[2]);

/*save it*/
$fp = fopen( $filename , 'w' ) ;
fputs( $fp , implode( '' , $array ) ) ;
fclose( $fp );
?>


note this is only efficient for small files , when dealing with big files the above method gets resource intensive & fseek etc is a beter option

[stophon4]

I am sending a deletion command for a line, but I am using a for loop variable. How do I retreive which line they chose to delete from the for loop?


$lines = count(file('guestbook.php')) + 1;
$filename = "guestbook.php";
$array= file( $filename ) ;
for ($i = 1; $i < $lines; ++$i)
{
echo "<form method='post' action='gb.php'><INPUT type='Submit' Name='delete' Value='Delete Post $i'></form>";
}