PHP将CSV文件转换为数组并相交

Question

I have six CSV files that I want to convert into individual arrays and then intersect those arrays to see all of the values that are similar in each. I have this so far:

 $directory = "/csv/CSS_AUDIT/";

 if (! is_dir($directory)) {
     exit('Invalid directory path');
 }

 $files = array();

 foreach (scandir($directory) as $file) {
     if ('.' === $file) continue;
     if ('..' === $file) continue;

     $files[] = $file;

      $row = 1;

     if (($handle = fopen("/csv/CSS_AUDIT/$file", "r")) !== FALSE) {
         while (($data = fgetcsv($handle, 1000, ",")) !== FALSE) {
             $num = count($data);
             $row++;
             for ($r=0; $r < $num; $r++) {
                 echo $data[$r];
                 if (!empty($data[$r])) 
                    echo "
";
             }
         }
         fclose($handle);
     }

 }

Right now it is looping through the files and giving me everything in one large array and I'm just kinda stuck. Any advice on how to achieve What I am trying to do?

Answer 1

If the files aren't too big, you can load them into an array and either check that such value doesn't exist in the array before adding to it, or running array_unique() when you're done. See this for a reference.

If the files are too big, you'll have to use some other more complicated and time-consuming methods (such as reading the (hopefully sorted) output each time before inserting new line).