PHP Variable handling

Example to check whether a given variable is an array

<?php

$yes = array('this', 'is', 'an array');

echo is_array($yes) ? 'Array' : 'not an Array';
echo "\n";

$no = 'this is a string';

echo is_array($no) ? 'Array' : 'not an Array';

?>

Output

Example to check whether given values are integer or not

<?php

$values = array(23, "23", 23.5, "23.5", null, true, false);

foreach ($values as $value)
{
    echo "is_int(";
    var_export($value);
    echo ") = ";
    var_dump(is_int($value));
}

?>

Output

Requirements

No external libraries are needed to build this extension.

Installation

There is no installation needed to use these functions; they are part of the PHP core.

Run-time Configuration

The behavior of these functions is affected by settings in php.ini.

Variables Configuration Options

Resource Types

This extension has no resource types defined.
 

Predefined Constants

This extension has no constants defined.

Variable handling functions

• boolval — Get the boolean value of a variable

• debug_zval_dump — Dumps a string representation of an internal zend value to output

• doubleval — Alias of floatval

• empty — Determine whether a variable is empty

• floatval — Get float value of a variable

• get_defined_vars — Returns an array of all defined variables

• get_resource_type — Returns the resource type

• gettype — Get the type of a variable

• import_request_variables — Import GET/POST/Cookie variables into the global scope

• intval — Get the integer value of a variable

• is_array — Finds whether a variable is an array

• is_bool — Finds out whether a variable is a boolean

• is_callable — Verify that the contents of a variable can be called as a function

• is_countable — Verify that the contents of a variable is a countable value

• is_double — Alias of is_float

• is_float — Finds whether the type of a variable is float

• is_int — Find whether the type of a variable is an integer

• is_integer — Alias of is_int

• is_iterable — Verify that the contents of a variable are an iterable value

• is_long — Alias of is_int

• is_null — Finds whether a variable is NULL

• is_numeric — Finds whether a variable is a number or a numeric string

• is_object — Finds whether a variable is an object

• is_real — Alias of is_float

• is_resource — Finds whether a variable is a resource

• is_scalar — Finds whether a variable is a scalar

• is_string — Find whether the type of a variable is a string

• isset — Determine if a variable is set and is not NULL

• print_r — Prints human-readable information about a variable

• serialize — Generates a storable representation of a value

• settype — Set the type of a variable

• strval — Get string value of a variable

• unserialize — Creates a PHP value from a stored representation

• unset — Unset a given variable

• var_dump — Dumps information about a variable

• var_export — Outputs or returns a parsable string representation of a variable