How to delete a line from the file with php?

Question

I have a file named $dir and a string named $line, I know that this string is a complete line of that file but I don\'t know its line number and I

Answer 1

this will just look over every line and if it not what you want to delete, it gets pushed to an array that will get written back to the file. see this

 $DELETE = "the_line_you_want_to_delete";

 $data = file("./foo.txt");

 $out = array();

 foreach($data as $line) {
     if(trim($line) != $DELETE) {
         $out[] = $line;
     }
 }

 $fp = fopen("./foo.txt", "w+");
 flock($fp, LOCK_EX);
 foreach($out as $line) {
     fwrite($fp, $line);
 }
 flock($fp, LOCK_UN);
 fclose($fp);