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PHP Array Exercises : Change the array values to upper or lower case

PHP Array: Exercise-12 with Solution

Write a PHP function to change the following array's all values to upper or lower case.

Sample arrays :
$Color = array('A' => 'Blue', 'B' => 'Green', 'c' => 'Red');

Sample Solution:

PHP Code:

<?php
function array_change_value_case($input, $ucase)
{
$case = $ucase;
$narray = array();
if (!is_array($input))
{
return $narray;
}
foreach ($input as $key => $value)
{
if (is_array($value))
{
$narray[$key] = array_change_value_case($value, $case);
 continue;
}
$narray[$key] = ($case == CASE_UPPER ? strtoupper($value) : strtolower($value));
}
return $narray;
}
$Color = array('A' => 'Blue', 'B' => 'Green', 'c' => 'Red');
echo 'Actual array 
'; print_r($Color); echo '
Values are in lower case.
'; $myColor = array_change_value_case($Color,CASE_LOWER); print_r($myColor); echo '
Values are in upper case.
'; $myColor = array_change_value_case($Color,CASE_UPPER); print_r($myColor); ?>

Sample Output:

Actual array Array                                          
(                                                           
    [A] => Blue                                             
    [B] => Green                                            
    [c] => Red                                              
)                                                           
Values are in lower case.Array                              
(                                                           
    [A] => blue                                             
    [B] => green                                            
    [c] => red                                              
)                                                           
Values are in upper case.Array                              
(                                                           
    [A] => BLUE                                             
    [B] => GREEN                                            
    [c] => RED                                              
)                   

Flowchart:

Flowchart: Change the array values to upper or lower case

PHP Code Editor:

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Previous: Write a PHP program to merge (by index) the specified two arrays.
Next: Write a PHP script which displays all the numbers between 200 and 250 that are divisible by 4.

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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