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PHP Variable Handling Functions

PHP Variable Handling Functions

The PHP variable handling functions are part of the PHP core. No installation is required to use these functions.

Function Description
boolval() Returns 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() Checks whether a 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 resource
gettype() Returns the type of variable
intval() Returns the integer value of a variable
is_array() Checks whether a variable is an array
is_bool() Checks whether a variable is a boolean
is_callable() Checks whether the contents of a variable can be called as a function
is_countable() Checks whether the contents of a variable is a countable value
is_double() Alias of is_float()
is_float() Checks whether a variable is of type float
is_int() Checks whether a variable is of type integer
is_integer() Alias of is_int()
is_iterable() Checks whether the contents of a variable is an iterable value
is_long() Alias of is_int()
is_null() Checks whether a variable is NULL
is_numeric() Checks whether a variable is a number or a numeric string
is_object() Checks whether a variable is an object
is_real() Alias of is_float()
is_resource() Checks whether a variable is a resource
is_scalar() Checks whether a variable is a scalar
is_string() Checks whether a variable is of type string
isset() Checks whether a variable is set (declared and not NULL)
print_r() Prints the information about a variable in a human-readable way
serialize() Converts a storable representation of a value
settype() Converts a variable to a specific type
strval() Returns the string value of a variable
unserialize() Converts serialized data back into actual data
unset() Unsets a variable
var_dump() Dumps information about one or more variables
var_export() Returns structured information (valid PHP code) about a variable