How to use count() function in PHP

PHPIt is often necessary to count the number of cells in an array or the number of attributes in an object. In this case, use count() correctly. Functions can quickly solve such troubles.

count() syntax

count  ( mixed $arr , [int $mode])

• $arr: Array or Countable Object.

• $mode: If the optional mode parameter is set to COUNT_RECURSIVE (or 1), count() The array will be counted recursively. Particularly useful for computing all elements of multidimensional arrays.

Return value: Returns the number of units in $arr.

Traversal of one-dimensional array:

<?php
$a[0] = 1;
$a[1] = 3;
$a[2] = 5;
var_dump(count($a));
?>

Traversal of two-dimensional array:

<?php
    $arr2 = array(&#39;apple&#39;, &#39;banana&#39;, array(&#39;cat&#39;, &#39;camel&#39;), &#39;dog&#39;);
    $count1 = count($arr2); // 4
    $count2 = count($arr2, 1); // 6
?>

Traversal of objects

<?php
class People {
  private $name;
  private $sex;
  private $age;
}
 
echo count(new People()); // 1
echo "<br>";
$p1=new People();
$c2 = count((array) $p1); 
echo $c2;// 3
?>

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