isset

(PHP 4, PHP 5, PHP 7)

issetDetermină dacă o variablă este stabilită și nu este NULL

Descrierea

bool isset ( mixed $var [, mixed $... ] )

Determină dacă o variablă este stabilită și nu este NULL.

Dacă o variabilă a fost eliminată cu unset(), ea nu va mai fi stabilită. isset() va întoarce FALSE la testarea unei variabile care a fost stabilită în NULL. De asemenea observați că caracterul nul ("\0") nu este echivalent cu constanta PHP NULL.

Dacă se furnizează mai mulți parametri, atunci isset() va întoarce TRUE numai dacă toți parametrii sunt stabiliți. Evaluarea se petrece de la stânga spre dreapta și se încheie de îndată ce se întâlnește o variabilă "ne-stabilită".

Parametri

var

Variabila ce va fi verificată.

...

O altă variabilă ...

Valorile întoarse

Întoarce TRUE dacă var există și are o valoare diferită de NULL. FALSE în caz contrar.

Istoricul schimbărilor

Versiune Descriere
5.4.0

Verificarea deplasamentelor non-numerice în șiruri de caractere acum întoarce FALSE.

Exemple

Example #1 Ecemple isset()

<?php

$var 
'';

// Aceasta va evalua în TRUE, de aceea textul va fi afișat.
if (isset($var)) {
    echo 
"This var is set so I will print.";
}

// În următoarele exemple vom utiliza var_dump pentru a afișa
// valoarea întoarsă de isset().

$a "test";
$b "anothertest";

var_dump(isset($a));      // TRUE
var_dump(isset($a$b)); // TRUE

unset ($a);

var_dump(isset($a));     // FALSE
var_dump(isset($a$b)); // FALSE

$foo NULL;
var_dump(isset($foo));   // FALSE

?>

Aceasta de asemenea funcționează și pentru elemente din tablouri:

<?php

$a 
= array ('test' => 1'hello' => NULL'pie' => array('a' => 'apple'));

var_dump(isset($a['test']));            // TRUE
var_dump(isset($a['foo']));             // FALSE
var_dump(isset($a['hello']));           // FALSE

// Cheia 'hello' este egală cu NULL, de aceea este considerată nesetată
// Dacă doriți să verificați cheile cu valori NULL, atunci încercați:
var_dump(array_key_exists('hello'$a)); // TRUE

// Verificarea valorilor la nivele mai adânci în tablou
var_dump(isset($a['pie']['a']));        // TRUE
var_dump(isset($a['pie']['b']));        // FALSE
var_dump(isset($a['cake']['a']['b']));  // FALSE

?>

Example #2 isset() cu deplasamente în șiruri de caractere

PHP 5.4 modifică modul cum funcționează isset() când îi sunt transmise deplasamente în șiruri de caractere.

<?php
$expected_array_got_string 
'somestring';
var_dump(isset($expected_array_got_string['some_key']));
var_dump(isset($expected_array_got_string[0]));
var_dump(isset($expected_array_got_string['0']));
var_dump(isset($expected_array_got_string[0.5]));
var_dump(isset($expected_array_got_string['0.5']));
var_dump(isset($expected_array_got_string['0 Mostel']));
?>

Exemplul de mai sus va afișa în PHP 5.3:

bool(true)
bool(true)
bool(true)
bool(true)
bool(true)
bool(true)

Exemplul de mai sus va afișa în PHP 5.4:

bool(false)
bool(true)
bool(true)
bool(true)
bool(false)
bool(false)

Note

Avertizare

isset() funcționează numai cu variabile, deoarece la furnizarea a orice altceva se va genera o eroare de interpretare. Pentru a verifica dacă constantele sunt stabilite utilizați funcția defined().

Notă: Deoarece aceasta este o construcție a limbajului și nu o funcție, ea nu poate fi apelată utilizând funcții de operare cu variabile .

Notă:

La utilizarea isset() asupra proprietăților inaccesibile ale obiectelor, va fi apelată metoda de supraîncărcare __isset(), dacă este declarată.

A se vedea și

add a note add a note

User Contributed Notes 55 notes

up
25
p_ignorethis_lbowers at gmail dot com
1 year ago
I, too, was dismayed to find that isset($foo) returns false if ($foo == null). Here's an (awkward) way around it.

unset($foo);
if (compact('foo') != array()) {
  do_your_thing();
}

Of course, that is very non-intuitive, long, hard-to-understand, and kludgy. Better to design your code so you don't depend on the difference between an unset variable and a variable with the value null. But "better" only because PHP has made this weird development choice.

In my thinking this was a mistake in the development of PHP. The name ("isset") should describe the function and not have the desciption be "is set AND is not null". If it was done properly a programmer could very easily do (isset($var) || is_null($var)) if they wanted to check for this!

A variable set to null is a different state than a variable not set - there should be some easy way to differentiate. Just my (pointless) $0.02.
up
47
beuc at beuc dot net
10 years ago
"empty() is the opposite of (boolean) var, except that no warning is generated when the variable is not set."

So essentially
<?php
if (isset($var) && $var)
?>
is the same as
<?php
if (!empty($var))
?>
doesn't it? :)

!empty() mimics the chk() function posted before.
up
42
yaogzhan at gmail dot com
12 years ago
in PHP5, if you have

<?PHP
class Foo
{
    protected
$data = array('bar' => null);

    function
__get($p)
    {
        if( isset(
$this->data[$p]) ) return $this->data[$p];
    }
}
?>

and
<?PHP
$foo
= new Foo;
echo isset(
$foo->bar);
?>
will always echo 'false'. because the isset() accepts VARIABLES as it parameters, but in this case, $foo->bar is NOT a VARIABLE. it is a VALUE returned from the __get() method of the class Foo. thus the isset($foo->bar) expreesion will always equal 'false'.
up
35
Daniel Klein
5 years ago
How to test for a variable actually existing, including being set to null. This will prevent errors when passing to functions.

<?php
// false
var_export(
 
array_key_exists('myvar', get_defined_vars())
);

$myvar;
// false
var_export(
 
array_key_exists('myvar', get_defined_vars())
);

$myvar = null;
// true
var_export(
 
array_key_exists('myvar', get_defined_vars())
);

unset(
$myvar);
// false
var_export(
 
array_key_exists('myvar', get_defined_vars())
);

if (
array_key_exists('myvar', get_defined_vars())) {
 
myfunction($myvar);
}
?>

Note: you can't turn this into a function (e.g. is_defined($myvar)) because get_defined_vars() only gets the variables in the current scope and entering a function changes the scope.
up
22
mandos78 AT mail from google
9 years ago
Careful with this function "ifsetfor" by soapergem, passing by reference means that if, like the example $_GET['id'], the argument is an array index, it will be created in the original array (with a null value), thus causing posible trouble with the following code. At least in PHP 5.

For example:

<?php
$a
= array();
print_r($a);
ifsetor($a["unsetindex"], 'default');
print_r($a);
?>

will print

Array
(
)
Array
(
    [unsetindex] =>
)

Any foreach or similar will be different before and after the call.
up
22
Anonymous
11 years ago
I tried the example posted previously by Slawek:

$foo = 'a little string';
echo isset($foo)?'yes ':'no ', isset($foo['aaaa'])?'yes ':'no ';

He got yes yes, but he didn't say what version of PHP he was using.

I tried this on PHP 5.0.5 and got:  yes no

But on PHP 4.3.5 I got:  yes yes

Apparently, PHP4 converts the the string 'aaaa' to zero and then returns the string character at that position within the string $foo, when $foo is not an array. That means you can't assume you are dealing with an array, even if you used an expression such as isset($foo['aaaa']['bbb']['cc']['d']), because it will return true also if any part is a string.

PHP5 does not do this. If $foo is a string, the index must actually be numeric (e.g. $foo[0]) for it to return the indexed character.
up
18
muratyaman at gmail dot com
9 years ago
To organize some of the frequently used functions..

<?php

/**
* Returns field of variable (arr[key] or obj->prop), otherwise the third parameter
* @param array/object $arr_or_obj
* @param string $key_or_prop
* @param mixed $else
*/
function nz($arr_or_obj, $key_or_prop, $else){
 
$result = $else;
  if(isset(
$arr_or_obj)){
    if(
is_array($arr_or_obj){
      if(isset(
$arr_or_obj[$key_or_prop]))
       
$result = $arr_or_obj[$key_or_prop];
    }elseif(
is_object($arr_or_object))
      if(isset(
$arr_or_obj->$key_or_prop))
       
$result = $arr_or_obj->$key_or_prop;
    }
  }
  return
$result;
}

/**
* Returns integer value using nz()
*/
function nz_int($arr_or_obj, $key_or_prop, $else){
  return
intval(nz($arr_or_obj, $key_or_prop, $else));
}

$my_id = nz_int($_REQUEST, 'id', 0);
if(
$my_id > 0){
 
//why?
}
?>
up
7
andreasonny83 at gmail dot com
2 years ago
Here is an example with multiple parameters supplied

<?php
$var
= array();
$var['val1'] = 'test';
$var['val2'] = 'on';

if ( isset(
$var['val1'], $var['val2'] ) && $var['val2'] === 'on' ) {
    unset(
$var['val1'] );
}
print_r( $var );
?>

This will output:
Array
(
    [val2] => on
)

The following code does the same calling "isset" 2 times:

<?php
$var
= array();
$var['val1'] = 'test';
$var['val2'] = 'on';

if ( isset(
$var['val1'] ) && isset( $var['val2'] ) && $var['val2'] === 'on' ) {
    unset(
$var['val1'] );
}
print_r( $var );
?>
up
16
francois vespa
6 years ago
Now this is how to achieve the same effect (ie, having isset() returning true even if variable has been set to null) for objects and arrays

<?php

// array

$array=array('foo'=>null);

return isset(
$array['foo']) || array_key_exists('foo',$array)
  ?
true : false ; // return true

return isset($array['inexistent']) || array_key_exists('inexistent',$array)
  ?
true : false ; // return false

// static class

class bar

{
  static
$foo=null;
}

return isset(
bar::$foo) || array_key_exists('foo',get_class_vars('bar'))
  ?
true : false ; // return true

return isset(bar::$inexistent) || array_key_exists('inexistent',get_class_vars('bar'))
  ?
true : false ; // return false

// object

class bar
{
    public
$foo=null;
}

$bar=new bar();

return isset(
$bar->foo) || array_key_exists('foo',get_object_vars($bar))
  ?
true : false ; // return true

return isset($bar->inexistent) || array_key_exists('inexistent',get_object_vars($bar))
  ?
true : false ; // return true

// stdClass

$bar=new stdClass;
$bar->foo=null;

return isset(
$bar->foo) || array_key_exists('foo',get_object_vars($bar))
  ?
true : false ; // return true

return isset($bar->inexistent) || array_key_exists('inexistent',get_object_vars($bar))
  ?
true : false ; // return true

?>
up
16
Andrew Penry
12 years ago
The following is an example of how to test if a variable is set, whether or not it is NULL. It makes use of the fact that an unset variable will throw an E_NOTICE error, but one initialized as NULL will not.

<?php

function var_exists($var){
    if (empty(
$GLOBALS['var_exists_err'])) {
        return
true;
    } else {
        unset(
$GLOBALS['var_exists_err']);
        return
false;
    }
}

function
var_existsHandler($errno, $errstr, $errfile, $errline) {
  
$GLOBALS['var_exists_err'] = true;
}

$l = NULL;
set_error_handler("var_existsHandler", E_NOTICE);
echo (
var_exists($l)) ? "True " : "False ";
echo (
var_exists($k)) ? "True " : "False ";
restore_error_handler();

?>

Outputs:
True False

The problem is, the set_error_handler and restore_error_handler calls can not be inside the function, which means you need 2 extra lines of code every time you are testing. And if you have any E_NOTICE errors caused by other code between the set_error_handler and restore_error_handler they will not be dealt with properly. One solution:

<?php

function var_exists($var){
   if (empty(
$GLOBALS['var_exists_err'])) {
       return
true;
   } else {
       unset(
$GLOBALS['var_exists_err']);
       return
false;
   }
}

function
var_existsHandler($errno, $errstr, $errfile, $errline) {
   
$filearr = file($errfile);
    if (
strpos($filearr[$errline-1], 'var_exists') !== false) {
       
$GLOBALS['var_exists_err'] = true;
        return
true;
    } else {
        return
false;
    }
}

$l = NULL;
set_error_handler("var_existsHandler", E_NOTICE);
echo (
var_exists($l)) ? "True " : "False ";
echo (
var_exists($k)) ? "True " : "False ";
is_null($j);
restore_error_handler();

?>

Outputs:
True False
Notice: Undefined variable: j in filename.php on line 26

This will make the handler only handle var_exists, but it adds a lot of overhead. Everytime an E_NOTICE error happens, the file it originated from will be loaded into an array.
up
14
a dot schaffhirt at sedna-soft dot de
9 years ago
You can safely use isset to check properties and subproperties of objects directly. So instead of writing

    isset($abc) && isset($abc->def) && isset($abc->def->ghi)

or in a shorter form

    isset($abc, $abc->def, $abc->def->ghi)

you can just write

    isset ($abc->def->ghi)

without raising any errors, warnings or notices.

Examples
<?php
    $abc
= (object) array("def" => 123);
   
var_dump(isset($abc));                // bool(true)
   
var_dump(isset($abc->def));           // bool(true)
   
var_dump(isset($abc->def->ghi));      // bool(false)
   
var_dump(isset($abc->def->ghi->jkl)); // bool(false)
   
var_dump(isset($def));                // bool(false)
   
var_dump(isset($def->ghi));           // bool(false)
   
var_dump(isset($def->ghi->jkl));      // bool(false)

   
var_dump($abc);                       // object(stdClass)#1 (1) { ["def"] => int(123) }
   
var_dump($abc->def);                  // int(123)
   
var_dump($abc->def->ghi);             // null / E_NOTICE: Trying to get property of non-object
   
var_dump($abc->def->ghi->jkl);        // null / E_NOTICE: Trying to get property of non-object
   
var_dump($def);                       // null / E_NOTICE: Trying to get property of non-object
   
var_dump($def->ghi);                  // null / E_NOTICE: Trying to get property of non-object
   
var_dump($def->ghi->jkl);             // null / E_NOTICE: Trying to get property of non-object
?>
up
14
anonymousleaf at gmail dot com
9 years ago
isset expects the variable sign first, so you can't add parentheses or anything.

<?php
    $foo
= 1;
    if(isset((
$foo))) { // Syntax error at isset((
       
$foo = 2;
    }
?>
up
14
Slawek Petrykowski
12 years ago
<?php
$foo
= 'a little string';
echo isset(
$foo)?'yes ':'no ', isset($foo['aaaa'])?'yes ':'no ';
>

results with unexpected values:
yes yes

Well
, it is necessary to check type of $foo first !
up
12
soywiz at php dot net
11 years ago
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2 years ago
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2 years ago
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        &bsp;  
->-&;   
->-pspat_span>[-&;    -lt">true?>->-&g>$errfi=/span>-&;   
->-lass="keyword">,get_object_vars'a/span>-gdlo_exists
  ?
->-&;p>$errfi=alassn     &nying to get property of non-object
   
->-lass="keyword">,get_object_vars'a/span>-gdlo_exists
  ?
!n class64442">
->def-&n class="comment">// bool(true)  &nying to get property of non-object
   
>'var_exists_err'  &nying to get property of non-object
        &
   
->-lass="keyword">,get_object_vars'a/span>-gdlo_exists
  ?
?>->-&g>$errfi=  &nying to get property of non-object
        &
      &bsp; &nbonly c64442">
->-lass="keyword">,get_object_vars'a/span>-gdlo_exists
  ?
!n class64442">
>'var_exists_err'  &nying to get property of non-object
        &
   
->
->-lass="keyword">,get_object_vars'a/span>-gdlo_exists
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!n class64442">
e 26

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soywiz at php dotmail dot com
9 years ago
isset expects the variable sign first, so you 57e=fu!g isset() returning true even if variable has bI knth91et ti iproba/>yln c ser reass="ddpanwarmalaExampl> soy$_REQUEST),e = Fnt"t an un, iet($abct.:span class="default">1$errfi=a">def-&_REQUEST>$errfi't wilt">true$filearr $errfi't wilt">truespan class="keyword">->
e 26
1$errfi=a@n class="default">$filearr $errfi't wilt">true?> e 26

ThI4-cavefunctiotypworll be pan /spagitnaiv copportunity io provide/aa_exs="v >t wil> <04-a6aas>&nbpanclavent"s_REQUEST
&nbpan><be down 03603
down 03603
soywiz at php dot3mail dot com
9 years ago
Here is an example with multiple parameters s03603e=ndd parentheses or anything.

'_exists, bspaa pspan> span cIfa span class="default">1
v claeT n class64442">
p r />Thpan>$errno      if/span>-&atl>$errfi) r />Thpan>Thpan>-&propan>$errfilegdloclass=
  ?
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,g/span>-&atl>$errfipan class="default">$filearr Thpan>Th} n clas n class64442">
-&xn>$errfileault">$bar$errfi(pa n class64442">
-&x>$errfiarray_key_exists,m>$errfile4 class="keyword">->< n clas n class64442">
-word">->def-&x>$errfiarray_key_exists, class="comment">// bool(true)
-word">->def-&x>$errfiarray_key_exists, class="comment">// bool(true)
-es"> n class64442"[EDITOR91hi"> NOTE: ICE esnippmple=fuimprove="des by "Pord Lashbrook"] id="Vu86313"> down 21461
down 21461
soywiz at php dot1mail dot com
9 years ago
Here is an example with multiple parameters s21461e=ng isset() returning true even if variable has bIfa ror, butt whgitnn e=fu2 /ies cr tiour> <04-at/a<inconed">en &spaconfunbsp="keyword">= It's/<04-just919"html">fanl>'isi72alists, but it s -into04-t.
caulsvf2008ablr they onbro> down 77060
down 77060
soywiz at php dotmail dot com
9 years ago
Here is an example with multiple parameters 77060fung isset() returning true even if variable has bI:&nslrn amplabl down 07820
down 07820
soywiz at php dot2mail dot com
9 years ago
Here is an example with multiple parameters s07820fung isset() returning true even if variable has bSin unn >fan: "Faamewgs="k: Ca/spa1
ass="default">$errno      if/span>-&// bool(true) {abr />def-&// bool(true)ass="defa=?> id="Vu863d="Vu86313"> down 661= soywiz at php dot3mail dot com
9 years ago
isset expects the variable sign first, so you 661=fu!g isset() returning true even if variable has bHere's/aasin unnass="defaable wil Sobr / but it > amp: pspan> span class="default">1
ass="default">$errno-&[Thp r />Thilea!">def-&[
$l $j[-lt">$l true$l $j
n class64442" n clasNow iet($abct. very popul>r ( be le span cilea!Srrnin: pspan> span cilea!issS down 2129g
down 2129g
soywiz at php dot-2mail dot com
2-mediea7266studies8-02-org10:16">9 years ago
Here is an example with multiple parameters s2129ge=nble is set, whether or not it is NULL. It makes useword">(tng> -http://whe.netrnotes-ven/Vd117266"> -
<throw is gs="kl Sobr / but it >wa <04-cla-at/a&l.pan>distoreuish/2 />'varathrough/2 lassays>&nbd">(ty
/>t ot whgs="klmessid=adiffeml.pan>dexistty "cla,"tincludv> "cla" by 2 lassays>&nbd">(.pan>Examp, etc.pan> r seadiffem clpponcepvsppan>b>/ser curn cl _exisi7266sment"ixamp, n />/ser _exisi7266 of>Examplisar dur_anp, bewith yn />Exclavpan>(266ts,abovev id="Vu86313"> down 95557
down 95557
soywiz at php dot0mail dot com
9 years ago
isset expects the variable sign first, so you95557e=ng isset() returning true even if variable has bHere's/aaniceem>ttunnass="defaao><'divhelpswbr /sivef-&=mlt12 > < >situa7266sem>so: pspan> span class="default">1
ift">def-&gpan>[Thp r />Thpan>-&bm>$errfile&gpan>[$jThp r />Thpan>-&bm>$errfilepan>[$j$errno[$errfipan class="default">$filearr < >$errfilelassn   Thp r />Thpan>def-&ntml">$errfi)w ?an class="default">$filearr >$errfi:esmlt12 > [$j
$errfile="sdlocspan>[
$errfi'first_#644lt">true$fkeyword"kEmpty>pan>[
-&tome"bsp;   &
    $errfile="sdlocspan>[
$errfi'tome"lt">true$flass="vot0pan>[
id="Vu863d="Vu86342"> down 12637
down 12637
soywiz at php dot-3mail dot com
9 years ago
Here is an example with multiple parameters s12637e=ng isset() returning true even if variable has b//">= nwadef<$_POST['foo'yw ?a$_POST['foo'y :l down 72077
down 72077
soywiz at php dot-2mail dot com
9 years ago
Here is an example with multiple parameters 72077e=ng isset() returning true even if variable has bBewarelao>ed/span>1
ass="default">$errno[[Thpan>def-&[Thpan>
[Th}span>$fkeyword"'> lt">true?><&gp>$errfi=amp;pa(o>?>->-&g>$errfio>?>[-&g>$errfi'blt">true?>->-&g>$errfio>$fkeyword"'> lt">true){pan culbsp; &bsp; &nemptyspan cultspan culttd">){pan culbsp; &bsp; &n>bl =s"> l
id="Vu863d="Vu86342"> down 20359
down 20359
soywiz at php dot-1mail dot com
9 years ago
Here is an example with multiple parameters s20359e=nble is set, whether or not it is NULL. It makes useault(=fuofm>soyso:span>1
only c64442">
$errfile$_GET>$errfi'clas't">true$fkeyword">nobody's">true
$errfile">def-&_GET>$errfi'clas't">true$filearr $errfi'clas't">truenobody's">true<br />$_GET['clas'y,a$_POST['clas'y,aynobody' only c64442">
$errfile$_GET>$errfi'clas't">true$flass="vot$_POST>$errfi'clas't">true$fkeyword">nobody's">true?> e 26

ThQudiv>,fromsng>http://whe.netrnotes-ven/migra726670.new-fe down 4805g
down 4805g
soywiz at php dot-mail dot com
,k8er tle="2008-02-25 10:16">9 years ago
Here is an example with multiple parameters 4805ge=nble is set, whether or not it is NULL. It makes ui iass="defai ivery claful whilantesti; < nbsbeo>sts,efacertaisu"tetfuofapplicatv66"/spanHrnd an"t an unat only cpan class="default">1$errfile$_GET>$errfi'c['];n/spanpan>$idu>$errfile$_GET>$errfi'id['];pan>$gs="kl>$errfilet mpl> truedef-&catpan>[Thpan>Thpan>def-&idpan>[Thpan>Thpan>$vakl>$errfilet mpl> $errfi.an class="default">$filearr $errfi.an class="default">$fkeyword">-'l>$errfi.an class="default">$filearr $errfi.an class="default">$fkeyword">atp"lt">true-&[Thpan>Thpan>-&[-&gs="kpan>[Thpan>$vakl>$errfilet mpl> $errfi.an class="default">$filearr $errfi.an class="default">$fkeyword">atp"lt">true-&[Thpan>Thpan>-&[-&gs="kpan>[t mpl> ive.lt">true-tp"pan>[?> e 26

ThY
seetseveralo>sts-t.
< is&nbsbeotestts,up66 opan cvpan>easilyspr ven &sly. Ostreric down 19050
down 19050
soywiz at php dot-2mail dot com
9 years ago
Here is an example with multiple parameters s19050funble is set, whether or not it is NULL. It makesRr />&nslTRUEanf>vaklord">,my1$errfi=/span>-lassn   Th/span>-&b>$errfi=/span>-FALSEn   $fass="defaul useoutapu
-TRUEn   Th/span>-&dpan>[lt">true?><&agt;pan>[def-&b>$errfi)):$fkeyword""TRUE>pan>[$fkeyword""FALSE>pan>[?> e 26
nbmrt nb"derityv id="Vu86313"> down 3620 soywiz at php dot-6mail dot com
9 years ago
isset expects the variable sign first, so you 3620fu!g isset() returning true even if variable has bBe th9a/>str by
edvtn is bs()nass="def; Iojust9wantts,divpointroutaa r visdefaablui imethod sinceait's/a biv>mengthavent"ro>doe = ICr eywck is&nbsrealizer /><t"rmin> < wbr /lt">$a=fusoona=fuit encount"r,my= gr />$><skip ov"rr nylr "20nf-&=ptml"s="keyword">= Iet($abct. p iv cd/>ce divdexisttis bs(),e 1$errfile">def-&_POST>$errfi' bu't">true-&_POST>$errfi' bu't">true?> e 26

ThAlsosbeowa> < nhnfuintosmpass="def,e down 55747
down 55747
soywiz at php dot-5mail dot com
9 years ago
isset expects the variable sign first, so you55747e=!g isset() returning true even if variable has bI: rorksa=fuexpeciv>: pspan> span class="default">1
ifbt">def-&objs64442">
array_key_exists= g>$errfi't">'t">true
array_key_exists= g>$errfi't">'t">true$j
n class64442" n clasI:<gla-a/faamewgs="kment"iv c>'var_)a pspan> span cICr rork arounbr : pspan> span class="default">1
ifbtsp;       retuis_td">){t;-&objs64442">
array_key_exists= g>$errfiw def-&objs64442">
array_key_exists= g>$errfi't">'t">true
array_key_exists= g>$errfi't">'t">true$j
id="Vu863d="Vu86313"> down 419= soywiz at php dot-10mail dot com
9 years ago
isset expects the variable sign first, so you 419=fu!g isset() returning true even if variable has bIplisapossiit > ivencapsul> < ass="()atests ietide/your> em cce ( tt wsmmpersy
(tlist) iet($abct. by >edv"ifs="<br />/ie> amp, o, buwise/aa_exs="v >str cpecifies8n t>sed/span>1
ass="default">$errno[$filearr $errfile->)r />Th{r />Thpan>def-&// bool(true) ?an class="default">$filearr $errfi:eskeywordpan>[?><&idu>$errfileint// bool(truetsp;       retuifs="-&_GET>$errfi'id[']pan class="default">$flass="vot0pan>[/span>?> id="Vu863d="Vu86313"> down 71518
down 71518
soywiz at php dot-10mail dot com
9 years ago
Here is an example with multiple parameters 71518e=ng isset() returning true even if variable has be wi:span>1[-100000t">true?><&kpan>[-&ipan>[-0t">true-&ipan>[-&qndpan>[-&ipan>[?><&kpan>[-&ipan>[-1t">true$feyword">-micro;ate{t;$fkeyword""\n>pan>[-&ipan>[-0t">true-&ipan>[-&qndpan>[-&ipan>[def-&kpan>[-&ipan>[$feyword">-micro;ate{t;$fkeyword""\n>pan>[-&ipan>[-0t">true-&ipan>[-&qndpan>[-&ipan>[-mp;pa_wordord">, class="comment">// bool(true-&ipan>[-&kpan>[$feyword">-micro;ate{t;$fkeyword""\n>pan>[-&ipan>[-0t">true-&ipan>[-&qndpan>[-&ipan>[-&kpan>[-&ipan>[-1t">true$feyword">-micro;ate{t;$fkeyword""\n>pan>[/span>?> e 26

Thbr /int"restoreares>:span> down 62790
down 62790
soywiz at php dot-10mail dot com
9 years ago
Here is an example with multiple parameters 62790fung isset() returning true even if variable has bBeente:span>i amplass="$numbern=a">def<$_GET['number'yw ?a$_GET['number'y : '';lass="&ggen=a">def<$_GET['gge'yw ?a$_GET['gge'y : '';lass="&re empl=a">def<$_GET['re emp'yw ?a$_GET['re emp'y : '';lass="r />ThAft"r: -arrayait's/easibuttbsreadspan>i amplass=" $"texmet"rr=amp;pa('number', 'gge', 're emp'o>Thpan>def<$_GET[$8644yw ?a$_GET[$8644y : '';lass=" }63d="Vu86313"> down 13641
down 13641
soywiz at php dot-5mail dot com
9 years ago
Here is an example with multiple parameters s13641fung isset() returning true even if variable has bKISS: mp;pa_wordord">,()>i oft"ntt wsmnswer, <04-ass="()cpan class="default">1){t;secur4lt">true->"span cil (e">defsgd">){t;secur4lt">true
}>?> id="Vu863d="Vu86313"> down 56751
down 56751
soywiz at php dot-10mail dot com
9 years ago
isset expects the variable sign first, so you56751fu!g isset() returning true even if variable has bIsdo/spaknow ifa mease):span>def< $v ))r />Thpan>go:span> down 79148
down 79148
soywiz at php dot-11mail dot com
9 years ago
Here is an example with multiple parameters 79148e=ng isset() returning true even if variable has bC 1$errfile=fs="-ʄpan>[$fkeyword">_exs="v #644lt">true=fs="[$filearr truedef-&[$filearr $errfi:eskeywordpan>[?> id="Vu863d="Vu86313"> down 76154
down 76154
soywiz at php dot-11mail dot com
9 years ago
Here is an example with multiple parameters 76154e=ng isset() returning true even if variable has bilt">def<$_POST['in_qu']))r />Thpan>def<$_GET['rq']))r />Thpan>def<$_POST['add_mnswer']))r />Thpan>def<$_GET['rq'])))r />Th{r />Thincludet"qanda/view_qandandef<$_POST['add_mnswer']))r3d="Vu86313"> down 4739g
down 4739g
soywiz at php dot-11mail dot com
9 years ago
Here is an example with multiple parameters 4739ge=ng isset() returning true even if variable has bUs= g>ass="pan>def<$gd">)[>t">']) span>ass="pan>def<$gd">)[>t">']['subt">']) span>$gd">)[>t">'] a keywor/ie>seemslao>' nfuuenvertts,div(int"ger) 0 y)[>t">']['subt">']ti ie bsp
ass="pan>_td">)<$gd">)[>t">']) def<$gd">)[>t">']['subt">'])span> ivshowdiui :span>1$errfiletd">)$fkeyword"> cl'l>$errfi=s"> ln class="default">$fkeyword"> bs1lt">truetwo'l>$errfi=s"> ln class="default">$fkeyword"> bs2lt">true$fkeyword"'$exu= 'pan>[-pywot_/{t;-&ext">true$fkeyword""> >pan>[/spaneg>$fkeyword"" ">def<\&ex[> cl']['tv> e'yw : >pan>[def-&ext">true cl't">truetv> e'pan>[$fkeyword"'true'pan>[$fkeyword"'lt">$lt">true$fkeyword""> >pan>[$fkeyword""">_td">)<\&ex[> cl']) def<\&ex[> cl']['tv> e'yw : >pan>[=s_td">){t;-&ext">true cl't">truedef-&ext">true cl't">truetv> e'pan>[$fkeyword"'true'pan>[$fkeyword"'lt">$lt">true?> e 26

Thshow :span><$exu= Ap;pag( [ cl] =s"> l bs1 [two] =s"> l bs2 )r />Th">def<$ex[> cl']['tv> e'yw : truer />Th">_td">)<$ex[> cl'])
def<$ex[> cl']['tv> e'yw : lt">$r3d="Vu86313"> down 98420
down 98420
soywiz at php dot-1mail dot com
n [-02]-25 10:16">9 years ago
Here is an example with multiple parameters 98420fung isset() returning true even if variable has bSin un,u be very claful:span>1
ass="default">$errno-&[$filearr $errfile$r3d="Vuan class="keyword">[def-&[$filearr $errfi:es?> e 26

ThSote/t an un :span>1
$errfiletrue-&bl>$errfiletrue$feyword">-i O/{t;-&g>$errfi,/span>-i O/{t;-&b>$errfi,/span>-3pan>[?> e 26<>$errfiletrue$feyword">-i O/{t;-&g>$errfi,/span>-i O/{t;-&b>$errfi,/span>-3pan>[?> e 26<>[$feyword">-i O/{t;-&g>$errfi,/span>-i O/{t;-&b>$errfi,/span>-3pan>[/span>?> id="Vu863d="Vu86313"> down 06494
down 06494
soywiz at php dot-15mail dot com
9 years ago
Here is an example with multiple parameters s06494e=ng isset() returning true even if variable has bIplisad">th <04= gr /> cce of a wor wbr i6 if td">),pbrgardun s-t. it's/contentsw clashaulsv,()><04-ass="()vpan><(correctly)pbr />$ai.
ap;pagwor isaspan,ewhich mpagbe/aaperfectly bsid/conditv66"<3d="Vu86313"> down 18351
down 18351
soywiz at php dot-5mail dot com
9 years ago
isset expects the variable sign first, so youV18351fung isset() returning true even if variable has bWer>/a/ but it > amp y
$/span>,()>tbs> ord">,/span>1$errfile->"span cpan>defswxcl>$errfi) );lass="pan>, class="comment">// bool(truetruesGLOBALSl>$errfi) );lass="s?> e 26

ThOutpu$) bool(true)r3d="Vu86313"> down 04608
down 04608
soywiz at php dot-19mail dot com
9 years ago
Here is an example with multiple parameters s04608e=ng isset() returning true even if variable has bUsaful tbs> havr somr bspaat cpecime">dent"GET POST but it s pspan> span class="default">1
ass="default">$errnotruesmlt12 > 4u>$errfilelassn   Thpan>def-&> true-&> true$filearr 4u>$errfi:es> truesmlt12 > 4 class="keyword">->" >$j span cass="default">$errno$errfi-&[Thpan>$errno-&_GET>$errfi'-&[-i _-&_POST>$errfi'-&[pan>[$j
n class64442" n clasE an un r3d="Vu86313"> down 07844
down 07844
soywiz at php dot-21mail dot com
9 years ago
Here is an example with multiple parameters s07844e=ng isset() returning true even if variable has bJust9tbsreit12> 4uefaw/> . Us= g aa"rapperpass="defs"><gln12> 4ua Notic c>'un s- 'var but it >by > em cce,si6 which ca>$aiplisaiv cequi bsen &nbswri4= grus= g S===aspan (which a l04- ase r). Even8ifa by > em cce,s <gla-notic srus= g m="vidimensdefalamp;pasdwher< ass="()a$"<3d="Vu86313"> down 38073
down 38073
soywiz at php dot-18mail dot com
9 years ago
Here is an example with multiple parameters 38073e=ng isset() returning true even if variable has bSicce PHPs"><> $ssi6 opdbu, I oft"nte1
ilbt">def-&[-&[Thpan>= g>ass="n64442">
}span>?> e 26

ThInsshari,tnf> <gln12> 4uan gs="kmnf> 1/span>ilbt/span>-&[= g }span>?> e 26

That bup, a <04edsepanwher<, "><br />$ain$:span>1
ilbt">def-&[= g }span>?> e 26

ThC <= g both> ivse$ai. S
amp, ans, />ssomr">= g o, bu, />n Npan "kmFt">$ai>ssomr">= g I findavery claful a l04-t. <04-amp, PHPs"><nevereexecu tt wssecondsprr4-t. "t">def<$ 4uan gs="kmeit bu/span>a wean,ee.g.:span>1$errfi=bt">def-&[-&[$filearr $errfi:etrue?> id="Vu863d="Vu86313"> down 1770=
down 1770=
soywiz at php dot-6mail dot com
9 years ago
isset expects the variable sign first, so youV1770=fung isset() returning true even if variable has bIsfounbrsomr">= g int"restoreawhilr rorkoreawit ass="()ai:1$errfilepan>[span>-&bl>$errfilepan>[/span>?>< bu_dump{t;def-&g>$errfi,an class="default">$filearr $errfi))as&nsltruer />Thlass="n64442">
>'var_exists_err'$errfi)"span c>/span>?>< bu_dump{t;def-&g>$errfi,n class="default">$filearr $errfi))as&nsllt">$ (a expecied)"span c>/span>$errfiat n class="default">$filearr $errfiat n/span>?>< bu_dump{t;def-&g>$errfi,n class="default">$filearr $errfi))as&nsltrue! id="Vu863d="Vu86313"> down 2129=
down 2129=
soywiz at php dot-1mail dot com
2-medita"defstudies8-02-org10:16">9 years ago
isset expects the variable sign first, so youV2129=fung isset() returning true even if variable has bICr doc spasd /> amp y
amp,"s /><'ssnt. Addorea" <04-lass" "> r dunbanp, becaus< ass="($v)lisaiv cs644ua !p">_span($v)l:ong>http://tur.netrnotes-ven/typesvyou"teisefsn actume">dau ituconfus= g. Sote/might strr4-tbs>ou"laindilt"rminelao> amp,s<04-realiz= gr /> tbsbywor/outanh> amp tbslass,pan>def "><br />$,u be ntc down 86919
down 86919
soywiz at php dot-28mail dot com
9 years ago
isset expects the variable sign first, so you86919<$1
ass="default">$errno$errfi-&[def-&[$errno$r3d="Vuan class="keyword">[ alwpasd ... O, buwise/PHPs"ouls havr thrilbt/span>-&[-lt">$r3d="Vuan class="keyword">[$errno[soyisNot? A/a/class y
br />$errno$r3d="Vuan class="keyword">[?> e 26

ThTbr r asefaw/ye facelao>dadvic cin$yis:sdo/spasoyis_spanr ntt wssitum"defsthe>dand mad cent.63d="Vu86313"> down 5176=
down 5176=
soywiz at php dot-29mail dot com
9 years ago
isset expects the variable sign first, so you5176=fung isset() returning true even if variable has bile lasae=fusen &po">s bufuarom/a/entm, aplisaa pain= g m>soywi cenllow= g, sicce ass="()adoe t<04-> def<$entm_8644) ord"> y<eg>= g but it >m>soywiz a "lus, a keywor/containorea"0"s"><e bsp <> dand amp y&nsllt">$ efa
= g po">s bu/span>1
ass="default">$errno buf>$errfi<) {r />Thpan>$errno$errfi<) =fu/span>-&[Thpan>def-&_POST>$errfi'-&[-&_POST>$errfi'-&[===atrue$errno$r3d="Vuan class="keyword">[Thpan>$errno[?> e 26

Tht an un:pif(po"> buf('entm_8644','entm_messid=')) [at ]s3d="Vu86313">
down 53737
down 53737
soywiz at php dot-37mail dot com
&liam lee ATe="20010:16">9 years ago
isset expects the variable sign first, so you53737e=ng isset() returning true even if variable has bJust9a <04euefa
db p>laddent"iestoreai.
ord">, ycontainesuan gmpty "" keywor.nempty<)lisadesignaddent"io>d!empty<)lisa
oddent"iestoreaent"def"<0n-ompty but it s.63d="Vu86313"> downsect"Vd81375"> nadd9a <04edth='12' height='12'> &pmaadd9a <04e63dma" id=f="/ma63de1375">ail dode1375">