PHP如何迭代目录并合并在该名称的单个文件中以相同字符串结尾的所有文件

Question

Description:

I have a directory that contains a large number of files named as follows:

2013_11_weekly.csv 
2013_10_weekly.csv 
2013_08_weekly.csv 
2013_09_weekly.csv 
2013_11_any_string.csv 
2013_10_any_string.csv

Problem:

How can I iterate over the directory and merge all the files that end with the same string into single files?

The end result would be a directory containing the following files.

weekly.csv 
any_string.csv 
...

Research:

I have the following code snippet that merges all all files.

<?php

$files = glob("*.csv");
$out = fopen("merged_files.csv", "w");
foreach($files as $file){
    fwrite($out, file_get_contents($file));
}
fclose($out);
echo "files merged";

?>

How can I amend my script to achieve the above?

I know I may have to use an array function, a str_ function and possibly a regular expression function.

Answer 1

This is very simple, you must just figure out, how to fetch common name from filenames.

In my example, I split filename on 8th position (2013_11_weekly.csv becomes weekly.csv ):

$files = glob("*.csv");
$out = array();
foreach($files as $file) {
    $name = substr(basename($file), 8);
    if (!isset($out[$name])) {
        $out[$name] = fopen($name, "w");
    }
    fwrite($out[$name], file_get_contents($file));
}
foreach ($out as $f) {
    fclose($f);
}