PHP write post to file not working

Question

I am trying to get a simple form which will write to a file using php. But I am running into an error where whenever I try and write a value got through post, it writes '0' to the file instead of the value.

I have a form like the following:

<form method="post" action="test.php">
<input type="text" name="user" />
<input type="submit" value="submit"/>
</form>

And test.php gets the user from the form via:

$user = $_POST['user'];

I can display $user on the page fine, and I have been able to write strings to the file using fwrite fine as well. But whenever I fwrite($file,$user) the only thing written is a 0. What am I doing wrong?

`fwrite($user)`? You have to pass an already created handle to the function. — ComFreek, Nov 19 '12 at 21:48
Why don't you show us some file operation code? We can't help you fix file output problems without seting the code... — Mathieu Dumoulin, Nov 19 '12 at 21:48
Well, `fwrite()` takes two arguments, `$resource` which is the file handler, and `$string` to write. You only pass one. — Madara's Ghost, Nov 19 '12 at 21:49
try `print_r($_POST);` see what you get back for the whole post: see http://stackoverflow.com/questions/7093363/php-how-to-print-r-post-array — keeg, Nov 19 '12 at 21:51
Sorry, I updated the original post. It turns out I had a typo when adding a new line to $user. I feel very stupid. Thanks everyone. — ztnewman, Nov 19 '12 at 21:59

score 3 · Answer 1 · edited Nov 19 '12 at 21:51

3

Are you missing the file handle,not the file, in fwrite

$user = $_POST['user'];
$fh = fopen("file.txt","a");
fwrite($fh,($user."\r\n")); // add newline for next time
fclose($fh);

edited Nov 19 '12 at 21:51

ComFreek

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answered Nov 19 '12 at 21:50

Samuel Cook

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This helped, I had the wrong syntax for adding a new line. :( – ztnewman Nov 19 '12 at 22:00
It's always the simple mistakes that drive you crazy – Samuel Cook Nov 19 '12 at 22:01

score 0 · Answer 2 · answered Nov 19 '12 at 21:52

0

You can also simply use file_put_contents with FILE_APPEND flag:

<?php 
if($_SERVER['REQUEST_METHOD']=='POST'){
    if(!empty($_POST['user'])){
        file_put_contents('file.txt',trim($_POST['user'])."\n",FILE_APPEND);
    }
}
?>

answered Nov 19 '12 at 21:52

Lawrence Cherone

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PHP write post to file not working

2 Answers2