PHP ZipArchive deleteIndex() Function

<?php

    // Create a new ZipArchive object
    $zip = new ZipArchive;

    // Check for opening the zip file
    if ($zip->open('Geeks.zip', ZipArchive::CREATE)) {

        if($zip->deleteIndex(2)) {
            echo 'File deleted successfully';
        } else {
            echo 'File not deleted';
        }

        // Close the zip file
        $zip->close();
    }
    // If zip file is not open/exist
    else 
    {
        echo 'Failed to open zip file';
    }
?>

<?php

    // Create a new ZipArchive object
    $zip = new ZipArchive;

    // Check for opening the zip file
    if ($zip->open('Geeks.zip', ZipArchive::CREATE)) {

        // Create new txt file and
        // add String to the file
        $zip->addFromString(
            'GFG1.txt', 
            'Welcome to GeeksforGeeks'
        );

        $zip->addFromString(
            'GFG2.txt', 
            'A computer science portal'
        );

        $zip->addFromString(
            'GFG3.txt', 
            'Welcome to GeeksforGeeks'
        );
    
      if($zip->deleteIndex(2)) 
      {
          echo 'File deleted successfully';
      } 
      else 
      {
          echo 'File not deleted';
      }

      // Close the zip file
      $zip->close();
  }
     // If zip file is not open/exist
  else
  {
     echo 'Failed to open zip file';
   }
?>