I don't understand why this expression doesn't work:
$var= '$_POST';
$name= ${$var}[name];
the ${$var}[name] expression wont return the same expression of
$_POST[name].
why does it happens, and how can i solve it?
thanks
On Sep 15, 10:32 am, Gandalf
> I don't understand why this expression doesn't work:
>
> $var= '$_POST';
>
> $name= ${$var}[name];
>
> the ${$var}[name] expression wont return the same expression of
> $_POST[name].
> why does it happens, and how can i solve it?
>
> thanks
i meant to write $var ='_POST',
and the that ${$var}[name] wont return the same value as $_POST[name]
Gandalf wrote:
> On Sep 15, 10:32 am, Gandalf
>> I don't understand why this expression doesn't work:
>>
>> $var= '$_POST';
>>
>> $name= ${$var}[name];
>>
>> the ${$var}[name] expression wont return the same expression of
>> $_POST[name].
>> why does it happens, and how can i solve it?
>>
>> thanks
>
> i meant to write $var ='_POST',
> and the that ${$var}[name] wont return the same value as $_POST[name]
>
hi
this should work as expected. Care to post more code?
--
gosha bine
extended php parser ~ http://code.google.com/p/pihipi
blok ~ http://www.tagarga.com/blok
On Sep 15, 11:07 am, gosha bine
> Gandalf wrote:
> > On Sep 15, 10:32 am, Gandalf
> >> I don't understand why this expression doesn't work:
>
> >> $var= '$_POST';
>
> >> $name= ${$var}[name];
>
> >> the ${$var}[name] expression wont return the same expression of
> >> $_POST[name].
> >> why does it happens, and how can i solve it?
>
> >> thanks
>
> > i meant to write $var ='_POST',
> > and the that ${$var}[name] wont return the same value as $_POST[name]
>
> hi
>
> this should work as expected. Care to post more code?
>
> --
> gosha bine
>
> extended php parser ~http://code.google.com/p/pihipi
> blok ~http://www.tagarga.com/blok
$var gets the value '_POST'
function create_par($var){
global $_COOKIE, $_POST, $active;
if(${$var}[no_win_from]!=0 || ${$var}[no_win_to]!=${$var}[games])
$active[0]="no_win"; else die(${$var}[games]);
if(${$var}[out_win_from]!=0 || ${$var}[out_win_to]!=${$var}[games])
$active[1]="out_win";
if(${$var}[yedaActive_2]=="true"){
if(${$var}[range_yeda1_from]!=0 || ${$var}[range_yeda1_to]!=${$var}
[games])$active[2]="range_yeda1";
}
if(${$var}[yedaActive_3]=="true"){
if(${$var}[range_yeda2_from]!=0 || ${$var}[range_yeda2_to]!=${$var}
[games]) $active[3]="range_yeda2";
}
if(${$var}[home_win_from]!=0 || ${$var}[home_win_to]!=${$var}[games])
$active[4]="home_win";
}
..oO(Gandalf)
>$var gets the value '_POST'
>function create_par($var){
> global $_COOKIE, $_POST, $active;
$_COOKIE, $_POST etc. are always available, no need to use 'global' on
them. But:
| Please note that variable variables cannot be used with PHP's
| Superglobal arrays within functions or class methods.
Micha
Michael Fesser wrote:
> | Please note that variable variables cannot be used with PHP's
> | Superglobal arrays within functions or class methods.
I read that, and re-read it, and re-read it... and I can't figure out
what it means. Can you re-phrase it?
I was good right up to "within functions...". I use super globals
within functions all the time.
..oO(Sanders Kaufman)
>Michael Fesser wrote:
>
>> | Please note that variable variables cannot be used with PHP's
>> | Superglobal arrays within functions or class methods.
>
>I read that, and re-read it, and re-read it... and I can't figure out
>what it means. Can you re-phrase it?
>
>I was good right up to "within functions...". I use super globals
>within functions all the time.
A variable variable is something like that:
$foo = 'bar';
$bar = 42;
print ${$foo}; // prints 42
This means the name of the variable is taken from another (string)
variable. The same can be done with superglobals, but not if you're
inside a function or method:
function test() {
$foo = '_GET';
var_dump(${$foo}); // throws a notice
}
Micha
Michael Fesser wrote:
> A variable variable is something like that:
>
> $foo = 'bar';
> $bar = 42;
>
> print ${$foo}; // prints 42
>
> This means the name of the variable is taken from another (string)
> variable. The same can be done with superglobals, but not if you're
> inside a function or method:
>
> function test() {
> $foo = '_GET';
> var_dump(${$foo}); // throws a notice
> }
I think that what's confusing me is that double-dollar thing.
I've seen it before, but thought it was a typo.
Could you tell me what it means, or where to look in the docs to find
out about it.
..oO(Sanders Kaufman)
>I think that what's confusing me is that double-dollar thing.
>I've seen it before, but thought it was a typo.
>
>Could you tell me what it means, or where to look in the docs to find
>out about it.
It's called a variable variable. As said - instead of accessing a
variable directly, it's done by taking the name of the variable from
_another_ string variable:
$foo = 42;
print $foo; // prints 42
$bar = 'foo';
print ${$bar}; // prints 42, too
The latter accesses a variable whose name is stored in another variable.
http://www.php.net/manual/en/language.variables.variable.php
Usuallly it's considered bad style to use variable variables, in most
cases there's a better way. But there's a similar thing that can be
really helpful - variable class names, i.e. the class name is stored in
a variable:
$foo = 'TMyClass';
$bar = new $foo(); // creates an instance of the class TMyClass
Micha
Michael Fesser wrote:
> It's called a variable variable. As said - instead of accessing a
> variable directly, it's done by taking the name of the variable from
> _another_ string variable:
Oh, WOW!!! That is so cool.
I was kinda thinkin about doing something like that all hodge-podge with
"eval" statements, but figured it was too hair-brained.
> Usuallly it's considered bad style to use variable variables, in most
> cases there's a better way.
So... it is a little hair-brained, eh? :)
Still - I'll have some fun exploring that.
> But there's a similar thing that can be
> really helpful - variable class names, i.e. the class name is stored in
> a variable:
>
> $foo = 'TMyClass';
> $bar = new $foo(); // creates an instance of the class TMyClass
Now I'm confused again.
Maybe I'm applying Java logic here or something.
Why doesn't that just create a new string containing, 'TMyClass'?
..oO(Sanders Kaufman)
>Michael Fesser wrote:
>
>> But there's a similar thing that can be
>> really helpful - variable class names, i.e. the class name is stored in
>> a variable:
>>
>> $foo = 'TMyClass';
>> $bar = new $foo(); // creates an instance of the class TMyClass
>
>Now I'm confused again.
>Maybe I'm applying Java logic here or something.
>Why doesn't that just create a new string containing, 'TMyClass'?
Because PHP is not Java. ;)
In this case the name of the class is taken from the variable (notice
the parentheses after the variable name). The same can also be done with
functions, which is a common way to implement callback functions in PHP.
Micha
Sanders Kaufman wrote:
> Michael Fesser wrote:
>
>> A variable variable is something like that:
>>
>> $foo = 'bar';
>> $bar = 42;
>>
>> print ${$foo}; // prints 42
>>
>> This means the name of the variable is taken from another (string)
>> variable. The same can be done with superglobals, but not if you're
>> inside a function or method:
>>
>> function test() {
>> $foo = '_GET';
>> var_dump(${$foo}); // throws a notice
>> }
>
> I think that what's confusing me is that double-dollar thing.
> I've seen it before, but thought it was a typo.
>
> Could you tell me what it means, or where to look in the docs to find
> out about it.
Sanders,
Not unusual. It is confusing, and IMHO not a good programming
technique, IMHO.
--
==================
Remove the "x" from my email address
Jerry Stuckle
JDS Computer Training Corp.
jstucklex@attglobal.net
==================
Jerry Stuckle wrote:
> Sanders Kaufman wrote:
>> I think that what's confusing me is that double-dollar thing.
>> I've seen it before, but thought it was a typo.
>>
>> Could you tell me what it means, or where to look in the docs to find
>> out about it.
>
> Not unusual. It is confusing, and IMHO not a good programming
> technique, IMHO.
Yeah - after contemplating it, I think maybe it's an accident that the
PHP dev guys just decided to feature, rather than fix.