CODEWITHSUNDEEP
phpfile
dukevin
dukevin

Reputation: 23178

Reading a file and returning the line containing

I have a file that contains 100 highscores for a game I'm scripting.

1.2345, name1
1.3456, name2
1.4567, name3

for example.

With php, I need to get the content of the line nameX appears on so I can overwrite it if the new score is higher than the old score. Also I need to find out which line number nameX appears on so they know what place (ranking) they are in.

Which php functions should I look into so that I can make this work?

Upvotes: 1

Views: 115

Answers (3)

cwallenpoole
cwallenpoole

Reputation: 82028

You can either use fopen and fread or file for this one. Personally, I would opt for file as it sounds like this is a fairly small file to begin with.

$row = -1;
$fl = file( '/path/to/file' );

if( $fl )
{
    foreach( $fl as $i => $line )
    {
        // break the line in two. This can also be done through subst, but when 
        // the contents of the string are this simple, explode works just fine.
        $pieces = explode( ", ", $line );
        if( $pieces[ 1 ] == $name ) 
        {
            $row = $i;
            break;
        }
    }
    // $row is now the index of the row that the user is on.
    // or it is -1.
}
else
{
    // do something to handle inability to read file.
}

For good measure, the fopen approach:

// create the file resource (or return false)
$fl = fopen( '/path/to/file', 'r' );
if( !$fl ) echo 'error'; /* handle error */

$row = -1;
// reads the file line by line.
while( $line = fread( $fl ) )
{
    // recognize this?
    $pieces = explode( ", ", $line );
    if( $pieces[ 1 ] == $name ) 
    {
        // ftell returns the current line number.
        $row = ftell( $fl );
        break;
    }
}
// yada yada yada

Upvotes: 4

Darkerstar
Darkerstar

Reputation: 932

First you need to read all the file content out. Modifiy the line you desire, then put them all together back the file. This however will have performance and constitancy prolbems if you running scripts simultaneous.

Upvotes: 0

Ibu
Ibu

Reputation: 43810

Here is a link that i always recommend, and it never failed so far.

Files in php

From Link:

<?php 

// set file to read
$file = '/usr/local/stuff/that/should/be/elsewhere/recipes/omelette.txt' or die('Could not read file!'); 
// read file into array 
$data = file($file) or die('Could not read file!'); 
// loop through array and print each line 
foreach ($data as $line) { 
     echo $line; 
} 

?>

Upvotes: 2

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