PHP

gettype(mixed $value): string

Returns the type of the PHP variable value. For type checking, use is_* functions.

Possible values for the returned string are:

"boolean"
"integer"
"double" (for historical reasons "double" is returned in case of a float, and not simply "float")
"string"
"array"
"object"
"resource"
"resource (closed)" as of PHP 7.2.0
"NULL"
"unknown type"

Version	Description
7.2.0	Closed resources are now reported as `'resource (closed)'`. Previously the returned value for closed resources were `'unknown type'`.

Example #1 gettype() example

<?php

$data = array(1, 1., NULL, new stdClass, 'foo');

foreach ($data as $value) {
    echo gettype($value), "\n";
}

?>

The above example will output something similar to:

integer
double
NULL
object
string

get_debug_type() - Gets the type name of a variable in a way that is suitable for debugging
settype() - Set the type of a variable
get_class() - Returns the name of the class of an object
is_array() - Finds whether a variable is an array
is_bool() - Finds out whether a variable is a boolean
is_callable() - Verify that a value can be called as a function from the current scope.
is_float() - Finds whether the type of a variable is float
is_int() - Find whether the type of a variable is integer
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_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
function_exists() - Return true if the given function has been defined
method_exists() - Checks if the class method exists

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