PHP | IntlChar::islower() Function

The IntlChar::islower() function is an inbuilt function in PHP which is used to check whether the given input character is a lowercase character or not.

Syntax:

bool IntlChar::islower( $codepoint )

Parameter: This function accepts a single parameter $codepoint which is mandatory. The input parameter is a character, which is encoded as a UTF-8 string.

Return Value: If $codepoint is a lowercase character then it returns True, otherwise return False.

Below programs illustrate the IntlChar::islower() function in PHP:

Program 1:

PHP

<?php
// PHP code to illustrate IntlChar::islower()
// function

// Input data is character type
var_dump(IntlChar::islower("a"));
var_dump(IntlChar::islower("A"));
var_dump(IntlChar::islower("\u{0041}"));

// Input data is control character
var_dump(IntlChar::islower("\t"));

// Input data is string type
var_dump(IntlChar::islower("Geeksforgeeks"));

// Input data is number type
var_dump(IntlChar::islower("2018"));

// Input data is single digit
var_dump(IntlChar::islower("5"));

?>

Output:

bool(true) 
bool(false) 
bool(false) 
bool(false) 
NULL 
NULL 
bool(false) 

Note: If String and Numbers (except single digit number) are used as a parameter then it returns NULL.

Program 2:

PHP

<?php
// PHP code to illustrate IntlChar::islower()

// Declare an array $arr
$arr = array("a", "\u{FF41}", "A", "\u{0041}", "0", "\n", "123", "Geeks");

// \u{0041} is ASCII value of 'A'
// \u{FF41} is ASCII value of 'a'

// Loop run for every array element
foreach ($arr as $val){

    // Check each element as code point data
    var_dump(IntlChar::islower($val));
}
?>

Output:

bool(true) 
bool(true) 
bool(false) 
bool(false) 
bool(false) 
bool(false) 
NULL 
NULL 

Reference: http://php.net/manual/en/intlchar.islower.php