Exit
  • Global community
    • Language:
      • Deutsch
      • English
      • Español
      • Français
      • Português
  • 日本語コミュニティ
  • 한국 커뮤니티
0

Somethign between unset() and empty() (kinda)

LEGEND ,
Oct 09, 2006 Oct 09, 2006
If now empty() checks to see if a variable has something in it, what can I
use to just empty a variable, or am I even causing any needed work when I
use unset()?

--

TIA,

Jon Parkhurst
PriivaWeb
http://priiva.net.


TOPICS
Server side applications
400
Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 09, 2006 Oct 09, 2006
$variable_name = "" or am I missing something ?

--

Dave Buchholz
I-CRE8
www.i-cre8.co.uk
Skype ID: I-CRE8


"crash" <crash@bcdcdigital.com> wrote in message
news:egeei3$pqm$1@forums.macromedia.com...
If now empty() checks to see if a variable has something in it, what can I
use to just empty a variable, or am I even causing any needed work when I
use unset()?

--

TIA,

Jon Parkhurst
PriivaWeb
http://priiva.net.



Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 09, 2006 Oct 09, 2006
Dave Buchholz wrote:
> $variable_name = "" or am I missing something ?

$variable_name = '' sets the variable to an empty string.

unset($variable_name) removes the variable completely.

$var = 5;
echo $var.'<br />'; // displays 5
$var = '';
if (empty($var)) {
echo '$var contains no value<br />'; // <-- This will be displayed
}
unset($var);
if (isset($var)) {
echo '$var still exists<br />'; // <-- This won't be displayed
}
else {
echo '$var does not exist'; // <-- This will
}

--
David Powers
Adobe Community Expert
Author, "Foundation PHP for Dreamweaver 8" (friends of ED)
http://foundationphp.com/
Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 10, 2006 Oct 10, 2006
got it, thanks David

--

Dave Buchholz
I-CRE8
www.i-cre8.co.uk
Skype ID: I-CRE8


"David Powers" <david@example.com> wrote in message
news:egeje4$1vm$1@forums.macromedia.com...
Dave Buchholz wrote:
> $variable_name = "" or am I missing something ?

$variable_name = '' sets the variable to an empty string.

unset($variable_name) removes the variable completely.

$var = 5;
echo $var.'<br />'; // displays 5
$var = '';
if (empty($var)) {
echo '$var contains no value<br />'; // <-- This will be displayed
}
unset($var);
if (isset($var)) {
echo '$var still exists<br />'; // <-- This won't be displayed
}
else {
echo '$var does not exist'; // <-- This will
}

--
David Powers
Adobe Community Expert
Author, "Foundation PHP for Dreamweaver 8" (friends of ED)
http://foundationphp.com/


Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 13, 2006 Oct 13, 2006
Thanks guys, I missed marking this and thus missed the response.

I don't know why, I was just expecting a "set0val" or some such thing.

Is there a difference between $var='' and $var=""?


"crash" <crash@bcdcdigital.com> wrote in message
news:egeei3$pqm$1@forums.macromedia.com...
> If now empty() checks to see if a variable has something in it, what can I
> use to just empty a variable, or am I even causing any needed work when I
> use unset()?
>
> --
>
> TIA,
>
> Jon Parkhurst
> PriivaWeb
> http://priiva.net.
>


Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 13, 2006 Oct 13, 2006
crash wrote:
> Is there a difference between $var='' and $var=""?

No.

--
David Powers
Adobe Community Expert
Author, "Foundation PHP for Dreamweaver 8" (friends of ED)
http://foundationphp.com/
Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 17, 2006 Oct 17, 2006
David,

Can you tell me either what to look for, or why a value is different if
echo'd from a function rather than returned from a function?

I can't remember what the term is to look for.

I'm sure i'll find it somewhere today.

Jon

"David Powers" <david@example.com> wrote in message
news:egp2p1$21s$1@forums.macromedia.com...
> crash wrote:
>> Is there a difference between $var='' and $var=""?
>
> No.
>
> --
> David Powers
> Adobe Community Expert
> Author, "Foundation PHP for Dreamweaver 8" (friends of ED)
> http://foundationphp.com/


Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 17, 2006 Oct 17, 2006
crash wrote:
> Can you tell me either what to look for, or why a value is different if
> echo'd from a function rather than returned from a function?

They should be the same, as long as you assign the value returned from
the function to a variable.

> I can't remember what the term is to look for.

You're probably thinking about variable scope. The value of variables
inside a function are limited in scope to inside the function. The only
exceptions are when the value is passed by reference or when the global
keyword is used inside the function.

--
David Powers
Adobe Community Expert
Author, "Foundation PHP for Dreamweaver 8" (friends of ED)
http://foundationphp.com/
Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 17, 2006 Oct 17, 2006
What I was doing was this:

Before (& now) I had somethign like this:
fucntion create_picture($l:link from database (to pic), $m:pic size){
$l='<img src="image_generator.php?img='.$l.'sz='.$m.'">';
return $l
}

$picture=create_picture($l, $m);
echo $picture;

What I tried to do was simple remove the return and place the echo inside
the function.

What hapened was :

External Echo:
good picture, result: image.php?img=Whatever.jpg&sz=thumb

Inside Echo:
no picture, result: image.php?img=Whatever.jpg&sz=thumb

When I echoed inside the function, it looks like my encapsulation was shot.
My image would not produce b/c my php was not picking up on the second
variable.



Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines
LEGEND ,
Oct 17, 2006 Oct 17, 2006
LATEST
gads, but i've been out of school too long. i should have used print, not
echo.

<hangs head>

"Crash" <crash@cdcdigitalBLAG.com> wrote in message
news:eh31pm$oii$1@forums.macromedia.com...
> What I was doing was this:
>
> Before (& now) I had somethign like this:
> fucntion create_picture($l:link from database (to pic), $m:pic size){
> $l='<img src="image_generator.php?img='.$l.'sz='.$m.'">';
> return $l
> }
>
> $picture=create_picture($l, $m);
> echo $picture;
>
> What I tried to do was simple remove the return and place the echo inside
> the function.
>
> What hapened was :
>
> External Echo:
> good picture, result: image.php?img=Whatever.jpg&sz=thumb
>
> Inside Echo:
> no picture, result: image.php?img=Whatever.jpg&sz=thumb
>
> When I echoed inside the function, it looks like my encapsulation was
shot.
> My image would not produce b/c my php was not picking up on the second
> variable.
>
>
>


Translate
Report
Community guidelines
Be kind and respectful, give credit to the original source of content, and search for duplicates before posting. Learn more
community guidelines