On this page, functions are enlisted to handle the variables in PHP. No installation is required as they are part of the core language.

boolval()Returns the boolean value of a variable
debug_zval_dump()Dump string representation of an internal zend value to output
doubleval()Alias of floatval()
empty()Check if variable is empty
floatval()Returns the float value of a variable
get_defined_vars()Returns all defined variables, as an array
get_resource_type()Returns the type of a resource
gettype()Returns the type of a variable
intval()Returns the integer value of a variable
is_array()Checks whether a variable is an array
is_bool()Checks if variable is a boolean
is_callable()Check if the contents of a variable can be called a function
is_countable()Checks if contents of a variable is a countable value
is_double()Alias of is_float()
is_float()Checks if variable is of type float
is_int()Checks if variable is of type integer
is_integer()Alias of is_int()
is_iterable()Check if contents of a variable is an iterable value
is_long()Alias of is_int()
is_null()Checks if variable is NULL
is_numeric()Check if variable is a number or a numeric string
is_object()Checks if variable is an object
is_real()Alias of is_float()
is_resource()Checks if variable is a resource
is_scalar()Checks if variable is a scalar
is_string()Check if variable is of type string
isset()Checks if variable is set (declared and not NULL)
print_r()Print the information about a variable in a human-readable way
serialize()Convert storable representation of a value
settype()Convert variable to a specific type
strval()Returns the string value of a variable
unserialize()Convert serialized data back into actual data
unset()Unset a variable
var_dump()Dump information about one or more variables
var_export()Returns structured information (valid PHP code) about a variable
Variable handling functions in PHP