w3resource

PHP Array Exercises : Count the total number of times a specific value appears in an array

PHP Array: Exercise-37 with Solution

Write a PHP script to count the total number of times a specific value appears in an array.

Sample Solution:

PHP Code:

<?php
function count_array_values($my_array, $match) 
{ 
    $count = 0; 
    
    foreach ($my_array as $key => $value) 
    { 
        if ($value == $match) 
        { 
            $count++; 
        } 
    } 
    
    return $count; 
} 

$colors = array("c1"=>"Red", "c2"=>"Green", "c3"=>"Yellow", "c4"=>"Red");

echo "\n"."Red color appears ".count_array_values($colors, "Red"). " time(s)."."\n"; 
?>

Sample Output:

Red color appears 2 time(s).

Flowchart:

Flowchart: PHP - Count the total number of times a specific value appears in an array

PHP Code Editor:

Contribute your code and comments through Disqus.

Previous: Write a PHP script to lower-case and upper-case, all elements in an array.
Next: Write a PHP function to create a multidimensional unique array for any single key index.

What is the difficulty level of this exercise?



PHP: Tips of the Day

Convert a PHP object to an associative array

Just typecast it

$array = (array) $yourObject;

From Arrays:

If an object is converted to an array, the result is an array whose elements are the object's properties. The keys are the member variable names, with a few notable exceptions: integer properties are unaccessible; private variables have the class name prepended to the variable name; protected variables have a '*' prepended to the variable name.These prepended values have null bytes on either side.

Example: Simple Object

$object = new StdClass;
$object->foo = 1;
$object->bar = 2;

var_dump( (array) $object );

Output:

array(2) {
  'foo' => int(1)
  'bar' => int(2)
}

Example: Complex Object

class Foo
{
    private $foo;
    protected $bar;
    public $baz;

    public function __construct()
    {
        $this->foo = 1;
        $this->bar = 2;
        $this->baz = new StdClass;
    }
}

var_dump( (array) new Foo );

Output (with \0s edited in for clarity):

array(3) {
  '\0Foo\0foo' => int(1)
  '\0*\0bar' => int(2)
  'baz' => class stdClass#2 (0) {}
}

Output with var_export instead of var_dump:

array (
  '' . "\0" . 'Foo' . "\0" . 'foo' => 1,
  '' . "\0" . '*' . "\0" . 'bar' => 2,
  'baz' =>
  stdClass::__set_state(array(
  )),
)

Typecasting this way will not do deep casting of the object graph and you need to apply the null bytes (as explained in the manual quote) to access any non-public attributes. So this works best when casting StdClass objects or objects with only public properties. For quick and dirty (what you asked for) it's fine.

Also see this in-depth blog post:

  • Fast PHP Object to Array conversion

Ref : https://bit.ly/3fqiV2E