PHP | IntlChar::isalpha() Function

The IntlChar::isalpha() function is an inbuilt function in PHP which is used to check the given input is an alphanumeric character or not.

Syntax:

bool IntlChar::isalpha( $codepoint )

Parameters: The IntlChar::isalpha() function accept single parameter $codepoint which is mandatory. The input parameter is an integer value or character, which is encoded as a UTF-8 string.
Return Value: If $codepoint is an alphanumeric character then it returns True, otherwise return False.

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

Program 1:

PHP

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

// Input data is character type
var_dump(IntlChar::isalpha("G"));

// Input data is string type
var_dump(IntlChar::isalpha("G\n"));

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

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

// Input data is single digit
var_dump(IntlChar::isalpha("5"));
?>

Output: 

bool(true) 
NULL 
NULL 
NULL 
bool(false)

Program 2:

PHP

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

// Declare an array $arr
$arr = array("G", "GeeksforGeeks", "^", "1001", "6", "\u{2018}");

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

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

Output: 

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

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