Predefined Constants
boolval
Variable handling
PHP Manual

# Variable handling Functions

## Table of Contents

- 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_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 integer
- is_integer — Alias of is_int
- 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 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

Predefined Constants
boolval
Variable handling
PHP Manual