How to count the number of elements in an array in PHP?

In PHP, you can use the built-in functions sizeof() and count() to calculate the number of elements in an array. This article will take you through these two functions and introduce the method of calculating the number of elements in an array. ,I hope to be helpful. [Video tutorial recommendation: PHP tutorial]

Method 1: PHP uses the sizeof() function to calculate the number of array elements Number

sizeof() function is an inbuilt function in PHP that is used to count the number of elements present in an array or any other countable object.

Basic syntax:

int sizeof(array，mode);

Parameters: sizeof() accepts two parameters

array: This parameter means that we Array of elements to be counted.

mode: This is an optional parameter that specifies the mode of the function. It can take two different values, as follows:

0: Default value, do not calculate all elements of multi-dimensional arrays

1: Indicates recursive calculation of arrays (calculation of multi-dimensional arrays All elements)

Return value: sizeof() function returns an integer value indicating the number of elements present in the array.

Let’s take an example to see how the izeof() function calculates the number of array elements.

Example 1: Count the number of elements in a one-dimensional array:

<?php 
   header("content-type:text/html;charset=utf-8");
   $a=array(1,2,3,4,5,6); 
  
   // 使用sizeof()计算数组中元素的个数
   $result = sizeof($a); 
  
   echo "数组中元素的个数为：".$result; 
?>

Output:

数组中元素的个数为：6

Example 2:Calculate the number of elements in a multidimensional array:

<?php 
header("content-type:text/html;charset=utf-8");
$array = array(&#39;name&#39; => array(&#39;php&#39;, &#39;hello&#39;, &#39;world&#39;), 
              &#39;article&#39; => array(&#39;sizeof&#39;, &#39;function&#39;, &#39;PHP&#39;)); 
  
// 递归计数
echo sizeof($array, 1)."<br>"; // 输出 8 
  
// 正常计数
echo sizeof($array); // 输出 2 
  
?>

Output:

8
2

Method 2: PHP uses the count() function to count the number of array elements

The count() function is used to count the current element in the array. The function may return 0 for variables that have been set to an empty array or 0 for variables that have not been set.

Basic syntax:

count(array，mode)

Parameters: The count() function usually takes one parameter, which represents the array whose elements need to be counted. But in addition, the function can also take parameter mode, which tells the function to count elements in normal or recursive mode.

array (mandatory): Represents an array whose elements need to be counted.

mode (optional): The mode used to set the function. This parameter can take two possible values:

0 (or False): the default value, which means not to calculate all elements of the multi-dimensional array

1: usually means to recursively calculate the array value; this helps with calculations on multidimensional arrays.

Return value: The count() function returns the number of elements in the array.

Example 1: Count the number of elements in a one-dimensional array:

<?php 
   header("content-type:text/html;charset=utf-8");
   $a=array(1,2,3,4,5,6); 
  
   // 使用sizeof()计算数组中元素的个数
   $result = count($a); 
  
   echo "数组中元素的个数为：".$result; 
?>

Output:

数组中元素的个数为：6

Example 2:Calculate the number of elements in a multidimensional array:

<?php 
header("content-type:text/html;charset=utf-8");
$array = array(&#39;name&#39; => array(&#39;php&#39;, &#39;hello&#39;, &#39;world&#39;), 
              &#39;article&#39; => array(&#39;count&#39;, &#39;function&#39;, &#39;PHP&#39;)); 
  
// 递归计数
echo count($array, 1)."<br>"; // 输出 8 
  
// 正常计数
echo count($array); // 输出 2 
  
?>

Output:

8
2

Description:

Calculating multidimensional arrays When counting the number of elements in the array, if you use the sizeof() or count() function directly (when the value of the mode parameter is 0), only the number of one-dimensional arrays will be counted, and the two-dimensional ones will be ignored. You need to set the value of the mode parameter to 1.

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