updating a file in specific part only in php - php

Question

I need to update a file using php
Sample file:
#Start#
No. of records: 2
Name: My name,
Age: 18,
Date: 2013-07-11||
Name: 2nd name,
Age: 28,
Date: 2013-07-11||
#End#
I need to edit 'No. of records' on each time I add another record on file. And another record needs to be before '#End#'
I'm using
$Handle = fopen($File, 'a');
$data = .......
fwrite($Handle, $Data);
to add records
How can I edit 'No. of records' & add data before '#End#'?

Answer 1

Instead of modifying the file I would parse it, change the data in PHP an rewrite the file after that.
To achieve this, I would firstly create a function that parses the input into php arrays:
function parse($file) {
$records = array();
foreach(file($file) as $line) {
if(preg_match('~^Name: (.*),~', $line, $matches)) {
$record = array('name' => $matches[1]);
}
if(preg_match('~^Age: (.*),~', $line, $matches)) {
$record ['age'] = $matches[1];
}
if(preg_match('~^Date: (.*)\|\|~', $line, $matches)) {
$record ['date'] = $matches[1];
$records [] = $record;
}
}
return $records;
}
Secondly I would create a function that flattens the arrays back into the same file format again:
function flatten($records, $file) {
$str = '#Start#';
$str .= "\n\n";
$str .= 'No. of records: ' . count($records) . "\n\n";
foreach($records as $record) {
$str .= 'Name: ' . $record['name'] . ",\n";
$str .= 'Age: ' . $record['name'] . ",\n";
$str .= 'Date: ' . $record['name'] . "||\n\n";
}
file_put_contents($file, $str . '#End#');
}
Then use it like this:
$records = parse('your.file');
var_dump($records);
$records []= array(
'name' => 'hek2mgl',
'age' => '36',
'date' => '07/11/2013'
);
flatten($records, 'your.file');

Answer 2

In case if file is relatively small (easily fits in memory), you can use file() function. It will return array, which you can iterate, etc.
If the file is larger, you'll need to read it in the loop using fgets(), writing data to the new temporary file and replacing original file with it after you're done