isSet()

[daGrevis]

Sveiki,

Vai...

 

if($x) {}

 

...būs pilnīgi tas pats, kas...

 

if(isSet($x)) {}

 

...?

 

Un esmu redzējis, ka daži dara šādi...

 

if($x and isSet($x)) {}

 

Kā būtu pareizāk?

[bobsters]

isset -- Determine whether a variable is set

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

 

Returns TRUE if varexists; FALSE otherwise.

 

If a variable has been unset with unset(), it will no longer be set. isset() will return FALSE if testing a variable that has been set to NULL. Also note that a NULL byte ("\0") is not equivalent to the PHP NULL constant.

 

Warning:

isset()

only works with variables as passing anything else will result in a parse error. For checking ifconstants are set use the

defined()

function.

Edited May 13, 2010 by bobsters

[daGrevis]

@bobsters

 

Aha, izcel vēl trakāk. =) Es neprasu ko dara isSet(), labi to zinu, es prasu, vai if($x) {} dara to pašu, ko isSet()!!! [facepalm]

[bobsters]

pārbaudi pats

 

$x=0;
if ($x){
echo "x ir uzlikts";
}
if (isset($x)){
echo "X ir parbaudits ar isset";
}

 

ar isset() viņš izvada tekstu

 

parasts if($x) neizvada neko

 

tātad secinam ka if ($x) nav jēgas

Edited May 13, 2010 by bobsters

[briedis]

nesapratu, ko bobster tur uzrakstīja, kaut aks dikti samurgots.

 

Atbildi varat atrast te: http://www.php.net/manual/en/types.comparisons.php

[daGrevis]

Paldies, briedis. Tādu atbildi arī cerēju saņemt... =)