Array is a commonly used data structure type, that is used to store values of any type. PHP allows storing different types of data in an array. Each element in an array can be accessed via its index number. While writing logics, the total length of an array needs to be calculated for various purposes.
To do so, PHP allows using two functions i.e., count() and sizeof(). There is absolutely no difference in these two functions, both will return the length of array. However, the recommended approach is to use count() more often, since sizeof() can create an illusion to some programmers of returning size in bytes or something which is not true.
HOW TO INITIALIZE AN ARRAY IN PHP Learn below
Table of Contents
Using count() to Calculate Length of an Array
- Create a .php file, and save it in C: > xampp > htdocs.
- Start Apache server for xampp control panel.
Let’s start coding.
<?php
//Demonstration of count()
$myarr = array('apple', 'mango', 'banana', 'peach');
$arrLen = count($myarr);
echo("Array Length calculated with Count(): ".$arrLen);
?> Here,
- array() is a built-in PHP method to define an array.
- echo() is again a built-in PHP method which is used to print the output on browser window.
- count() as discussed, will return the length of array.
Output
Using sizeof() to Calculate the Length of Array
The second approach to calculate the length of an array is to use sizeof() method on the array. See the example below.
<?php
//Demonstration of sizeof()
$myarr = array('apple', 'mango', 'banana', 'peach');
$arrLen = sizeof($myarr);
echo("Array Length calculated with sizeof(): ".$arrLen);
?> Output
Length Calculation of a Multidimensional Array
Multidimensional arrays are the arrays that contain one or more arrays within themselves. Let’s now see an example of multidimensional array and calculate its length in PHP.
<?php
//Multidimensional Array
$MDArray = array(
1,
2,
3,
4,
5,
array(
10,
20,
30
)
);
echo("Array Length calculated with Count(): ". count($MDArray, COUNT_RECURSIVE));
echo("<br/><br/>");
echo("Array Length calculated with sizeof(): ". sizeof($MDArray, COUNT_RECURSIVE));
echo("<br/><br/>");
echo("Multidimensional Array Length without using COUNT_RECURSIVE: ". count($MDArray));
?> COUNT_RECURSIVE
is used to tell the function to recursively dive into the array structure and count each entry, thus the methods will count all the elements of the array and the elements inside the array of an array. Without COUNT_RECURSIVE the methods will not count the elements of array that is inside the array.
Output
The first two outputs are 9, which means that the functions first counted the initial five elements, then the nested array itself, and then the elements inside the nested array. The last output returns an array length of 6, which means that it did not go inside the nested array and did not count its individual element.
Conclusion
In this article we discussed about the ways to calculate length of array in PHP. We practically observed two methods i.e., count() and sizeof() doing the same job, and later we finally implemented them on multidimensional arrays. We also observed what difference COUNT_RECURSIVE can make in determining the length of multidimensional arrays.