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PHP Array Exercises : Merge two arrays

PHP Array: Exercise-11 with Solution

Write a PHP program to merge (by index) the following two arrays.

Sample arrays :
$array1 = array(array(77, 87), array(23, 45));
$array2 = array("w3resource", "com");

Sample Solution:

PHP Code:

<?php
$array1 = array(array(77, 87), array(23, 45));
$array2 = array("w3resource", "com");
function merge_arrays_by_index($x, $y)
{
$temp = array(); $temp[] = $x; if(is_scalar($y))
{
$temp[] = $y;
}
else
{
foreach($y as $k => $v)
{
$temp[] = $v;
}
}
return $temp;
}
echo '<pre>'; print_r(array_map('merge_arrays_by_index',$array2, $array1));
?>

Sample Output: 

<pre>Array                                                  
(                                                           
    [0] => Array                                            
        (                                                   
            [0] => w3resource                               
            [1] => 77                                       
            [2] => 87                                       
        )                                                   
                                                            
    [1] => Array                                            
        (                                                   
            [0] => com                                      
            [1] => 23                                       
            [2] => 45                                       
        )                                                   
                                                            
)

Flowchart:

Flowchart: Merge two arrays

PHP Code Editor:

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Previous: Write a PHP program to sort an array of positive integers using the Bead-Sort Algorithm.
Next: Write a PHP function to change the specified array's all values to upper or lower case.

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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