Simple PHP Class to save an array to disk and read it back into a PHP Array using JSON.

JSONArrayFileUtil.php

<?php
/**
 * Save an PHP Array to disk with a delimiter to support
 * multiple array values. Associative Array supported.
 *
 * @author Jared Blalock (jared.blalock@gmail.com)
 * @link http://molotovbliss.com
 */
Class Json_Array {

  /**
   * Save array to Disk via JSON with delimiter
   *
   * @param string $file
   * @param array $data
   * @param string $delimiter
   * @return boolean 
   */
  public function saveArray($file, $data, $delimiter = '|') {
    $save = file_put_contents($file, json_encode($data).$delimiter, FILE_APPEND);
    if($save === FALSE) {
      return false;
    } else {
      return true;
    }
  }
  
  /**
   * Read saved aray back to PHP via JSON
   *
   * @param string $file
   * @param string $delimiter
   * @param boolean $returnAsArray
   * @return array|boolean $output
   */
  public function loadArray($file, $delimiter = '|', $returnAsArray = true) {
    $data = explode($delimiter, file_get_contents($file));
    if($data === FALSE) {
      return false;
    } else {
      foreach($data as $d) {
      	$output[] = json_decode($d, $returnAsArray);
      }
      return array_pop($output);
    }
  }

}

/**
 * EXAMPLE USAGE OF CLASS
 */

// Example Array
$testArray = array("Volvo", "BMW", "Toyota");
$testArray[] = "Dodge";

// Filename to save array data to
$filename = 'testarray.json';

// Array to store read of saved data
$dataFromDisk = array();

// Create Class Object
$jsonArray = new Json_Array;

// Save test array to disk
$jsonArray->saveArray($filename, $testArray);

// Read test array from disk
$dataFromDisk = $jsonArray->loadArray($filename);

// Output contents
if(!$dataFromDisk) {
  echo "Data not found.";
} else {
  print_r($dataFromDisk);
}