How to Compare Associative Rows of 2-Dimensional Arrays in PHP?

Compare Associative Rows of 2-Dimensional Arrays: A Comprehensive Guide

Multi-dimensional arrays are a powerful way to organize data in PHP, but comparing them can be a challenge. This question explores how to effectively compare associative rows of two 2-dimensional arrays using the array_diff_assoc() function.

Challenge:

The objective is to identify and extract the rows from $pageids that are not present in $parentpage. The array_diff_assoc() function is designed to compare associative arrays, but it operates on the first level of the arrays, ignoring the nested rows.

The Problem:

The code provided:

$pageWithNoChildren = array_diff_assoc($pageids,$parentpage);

returns incorrect results because it ignores the nested rows and only considers the keys of the first level.

Solution:

The proposed solution involves converting each sub-array to a string representation using serialize(). This transforms the multi-dimensional arrays into one-dimensional arrays:

$diff = array_diff(array_map('serialize', $pageids), array_map('serialize', $parentpage));

Subsequently, the differences are converted back into sub-arrays using unserialize():

$pageWithNoChildren = array_map('unserialize', $diff);

This method effectively compares the contents of the nested rows, resulting in the following expected output:

array (
  0 => 
  array (
    'id' => 1,
    'linklabel' => 'Home',
    'url' => 'home',
  ),
  3 => 
  array (
    'id' => 6,
    'linklabel' => 'Logo Design',
    'url' => 'logodesign',
  ),
  4 => 
  array (
    'id' => 15,
    'linklabel' => 'Content Writing',
    'url' => 'contentwriting',
  ),
)

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