Last updated: Fri, 27 Jun 2008

gettype

(PHP 4, PHP 5)

gettype — Resituisce il tipo di una variabile

Descrizione

string gettype ( mixed $var )

Restituisce il tipo della variabile PHP var .

Avviso

Non utilizzare gettype() per testare certi tipi di variabili poichè la stringa restistuita potrebbe variare nelle versioni future. Inoltre questa funzione è lenta dato che richiede confronti tra stringhe

Piuttosto utilizzare le funzioni is_*.

La stringa restituita può assumere i seguenti valori:

"boolean" (dalla versione 4 di PHP)
"integer"
"double" (per ragioni storiche viene restituito "double" in caso di variabile di tipo float, e non semplicemente "float")
"string"
"array"
"object"
"resource" (dalla versione 4 di PHP)
"NULL" (dalla versione 4 di PHP)
"user function" (soltanto in PHP 3, deprecated)
"unknown type"

Nella versione 4 di PHP si dovrebbe applicare alle funzioni function_exists() o method_exists() al posto del precedente gettype().

Vedere anche settype(), is_array(), is_bool(), is_float(), is_int(), is_null(), is_numeric(), is_object(), is_resource(), is_scalar() e is_string().

import_request_variables

get_resource_type

Last updated: Fri, 27 Jun 2008

add a note User Contributed Notes
gettype

skatebiker at hotmail dot com
22-Feb-2008 02:51


In some rare cases a class instance object returns false when an object but gettype() returns "object".



$x = new classvar();



$save = serialize($x);



......



$obj = unserialize($save);

// here sometimes is_object() returns FALSE

if (is_object($x) || gettype($x) === "object")

{

   ... do something

}

andrey at php dot net
17-Jul-2007 07:08


The function returns "unicode" for Unicode strings in PHP6.

sneskid at hotmail dot com
05-Mar-2007 10:56


I wrote my own gettype function by just using the default is_? functions, but it took twice as long as gettype... So I decided to use gettype with a twist.



Taking the warnings about gettype to heart, and depending on your custom needs, it's worthwhile to dynamically test the gettype result with a known variable, and link the result to a predefined result. Like so:



<?php

/*

 dynamically create an array by using known variable types

 link with a predefined value

*/

$R=array();

$R[gettype(.0)]='number';

$R[gettype(0)]='number';

$R[gettype(true)]='boolean';

$R[gettype('')]='string';

$R[gettype(null)]='null';

$R[gettype(array())]='array';

$R[gettype(new stdClass())]='object';



// what is

function wis_($v){

    global $R;

    return $R[gettype($v)];

}



echo wis_('hello') . '<br/>'; // "string"

echo wis_(24) . '<br/>'; // "number"

echo wis_(0.24) . '<br/>'; // "number"

echo wis_(null) . '<br/>'; // "null"

echo wis_($R) . '<br/>'; // "array"

?>

You won't need to worry about changes in gettype's return strings in future versions.

If the result evaluates to false then you know the variable tested is some "other" type.



I also find these useful

<?php

function is_num($v){return (is_int($v) || is_double($v));}

function is_box($v){return (is_array($v)||is_object($v));}



echo is_num(null) . '<br/>'; // false

echo is_num(false) . '<br/>'; // false

echo is_num('123') . '<br/>'; // false

echo is_num(123) . '<br/>'; // true

echo is_num(123.0) . '<br/>'; // true

?>

gilthansNOSPAM at gmail dot com
11-Sep-2005 10:18


NaN and #IND will return double or float on gettype, while some inexistent values, like division by zero, will return as a boolean FALSE. 0 by the 0th potency returns 1, even though it is mathematically indetermined.



<?php

$number = 5/0;

$number2 = sqrt(-3);

$number3 = pow(0, 0);

$number4 = 0/0;



echo $number."<br />";

echo $number2."<br />";

echo $number3."<br />";

echo $number4."<br />";

echo "<br />";

echo gettype($number)."<br />";

echo gettype($number2)."<br />";

echo gettype($number3)."<br />";

echo gettype($number4);

?>



This will return:



-1.#IND

1



boolean

double

integer

boolean



0

1

1

0

PHP Warning: Division by zero in C\test.php on line 2 PHP Warning: Division by zero in C:\test.php on line 5

matt at appstate
16-Dec-2004 08:10


Here is something that had me stumped with regards to gettype and is_object.

Gettype will report an incomplete object as such, whereas is_object will return FALSE.



if (!is_object($incomplete_obj)) {

   echo 'This variable is not an object, it is a/an ' . gettype($incomplete_obj);

}



Will print:

This variable is not an object, it is a/an object

jose at vocis dot com
14-Sep-2000 06:22


Also returns "NULL" for variables assigned the return of a function that returned no value via "return;". 





<code>





function weird(){


    return;


}


$a=weird();





</code>





isset($a) <> 1


empty($a) <> 1


gettype($a) == NULL





-Jose Batista

ojones at dotclick dot com
31-Aug-2000 07:19


After calling OCIResult to retrieve a NULL result from an Oracle result-set, gettype returns the string 'NULL'.

add a note

import_request_variables

get_resource_type

Last updated: Fri, 27 Jun 2008