[RESOLVED] Rating System

[lupus2k5]

OK, I have no idea how to do this. Basically I want to design a rating system for an image gallery I made and finally works.

Basically, in a file called preview.php, I need to display:
Rating: <?php echo $rating; ?>%
Rate It: ()1 ()2 ()3 ()4 ()5 [ Submit ] <- Submits to rate.php
()=radio button

Actually, that would probably be modified to a different form. But what I need is to save their rating into a flatfile (ratings.txt) and then for preview.php to display an average of all the ratings.

I haven't the slightest idea how to do this without a DB (which I don't have). I realize how to add to a flatfile via fopen, fwrite, fclose, but how do I read the contents and then average them?

[Jack_McSlay]

your could just call an fopen() in write-only mode in order to put the data, then everytime you want to calculate it you'll read the file you load the file, sum up the values stored in it and divide by the amount of reviews.

since the possible values for the review is only a single char (1 to 5) it should be quite easy to parse the data.

it would be something along those lines:

storing script:

$handle = fopen ('path/ratings.txt','w');
fwrite ($handle,$_POST['review_score']);
fclose ($handle);

reading script:

$file = join ('', file ('path/ratings.txt'));

$len = strlen ($file);
$avg = 0;
for ($x = 0;$x < $len;$x++) $avg += $file[$x];
$avg /= $len;

echo 'The average score is: '. $avg;

[lupus2k5]

Thanks, trying.

[lupus2k5]

I don't get it. If you're averaging a file that was written with 'w', won't you only be averaging one number?

And it didn't work; I just got an error saying I can't divide by zero. ??

[lupus2k5]

Nevermind, I fixed it.