Variable Variables in Classes

[Alan Little]

class example {
var $Stage;

function example() {
$this->Stage = 'init';

$x = ???????;

echo $$x;
}
}

What do I put in $x so that $$x gives me "init"? 'Stage' doesn't work,
nor does 'this->Stage'.

--
Alan Little
Phorm PHP Form Processor
http://www.phorm.com/

[Ambush Commander]

It looks like in this particular case, $this->$x should be sufficient.
Otherwise, you may have to split up x into $x_object and $x_name
(exploding by -> should be sufficient) and calling $x_object->$x_name.
What you currently have, however, cannot be done.

[Rik]

Alan Little wrote:

class example {
var $Stage;

function example() {
$this->Stage = 'init';

$x = ???????;

echo $$x;
}
}

What do I put in $x so that $$x gives me "init"? 'Stage' doesn't work,
nor does 'this->Stage'.

Why use the $$ syntax?

<?php

class test{
var $string;
function text(){
$this->string = "This works";
$check = 'string';
echo $this->$check;
}
}
$a = new test();
$a->text();
?>

Grtz,
--
Rik Wasmus

[Alan Little]

Carved in mystic runes upon the very living rock, the last words of
Ambush Commander of comp.lang.php make plain:

It looks like in this particular case, $this->$x should be sufficient.
Thanks, but no.
Otherwise, you may have to split up x into $x_object and $x_name
(exploding by -> should be sufficient) and calling $x_object->$x_name.
What you currently have, however, cannot be done.

I'm not sure what you mean. What I'm trying to do is parse variables out
of a string and substitute them with the value. $x (in this example)
would hold the variable name extracted from the string. I'm trying to
figure out how to get to the value of that variable, from there.

--
Alan Little
Phorm PHP Form Processor
http://www.phorm.com/

[Rik]

Alan Little wrote:

Carved in mystic runes upon the very living rock, the last words of
Ambush Commander of comp.lang.php make plain:

It looks like in this particular case, $this->$x should be
sufficient.

Thanks, but no.

Otherwise, you may have to split up x into $x_object and $x_name
(exploding by -> should be sufficient) and calling
$x_object->$x_name. What you currently have, however, cannot be done.

I'm not sure what you mean.
What I'm trying to do is parse variables
out of a string and substitute them with the value. $x (in this
example) would hold the variable name extracted from the string. I'm
trying to figure out how to get to the value of that variable, from
there.

That is exactly what it does.
$x = 'string'

$$x = $this->$x;
equals:
$string = $this->string;

$x is the variable name, $variable_name holds the value......

I don't get the problem?

What is the exact reason you're trying to accomplish? Maybe if you elaborate
some more, we get the picture. Why is it this doesn't suffice?

Grtz,
--
Rik Wasmus

[Alan Little]

Carved in mystic runes upon the very living rock, the last words of Rik
of comp.lang.php make plain:

Alan Little wrote:

Carved in mystic runes upon the very living rock, the last words of
Ambush Commander of comp.lang.php make plain:

It looks like in this particular case, $this->$x should be
sufficient.

Thanks, but no.

Otherwise, you may have to split up x into $x_object and $x_name
(exploding by -> should be sufficient) and calling
$x_object->$x_name. What you currently have, however, cannot be
done.

I'm not sure what you mean.
What I'm trying to do is parse variables
out of a string and substitute them with the value. $x (in this
example) would hold the variable name extracted from the string. I'm
trying to figure out how to get to the value of that variable, from
there.

That is exactly what it does.
$x = 'string'

$$x = $this->$x;
equals:
$string = $this->string;

$x is the variable name, $variable_name holds the value......

I don't get the problem?

What is the exact reason you're trying to accomplish? Maybe if you
elaborate some more, we get the picture. Why is it this doesn't
suffice?

For example:

$this->animal = 'lamb';
$this->string = 'Mary had a little {{animal}}';

The goal is to extract 'animal' from the string (no problem), convert it
to 'lamb' and replace it in the string (again, no problem). The question
is, if I have 'animal', how do I get 'lamb'? In global space, I would
simply have 'animal' in a variable, and use $$var to get 'lamb'.

--
Alan Little
Phorm PHP Form Processor
http://www.phorm.com/

[Alan Little]

Carved in mystic runes upon the very living rock, the last words of Rik
of comp.lang.php make plain:

Alan Little wrote:

class example {
var $Stage;

function example() {
$this->Stage = 'init';

$x = ???????;

echo $$x;
}
}

What do I put in $x so that $$x gives me "init"? 'Stage' doesn't work,
nor does 'this->Stage'.

Why use the $$ syntax?

<?php

class test{
var $string;
function text(){
$this->string = "This works";
$check = 'string';
echo $this->$check;

Ah, yes that works. Thank you.

--
Alan Little
Phorm PHP Form Processor
http://www.phorm.com/

[Kimmo Laine]

"Alan Little" <al**@n-o-s-p-a-m-phorm.com> wrote in message
news:Xn**************************@216.196.97.131.. .

Carved in mystic runes upon the very living rock, the last words of Rik
of comp.lang.php make plain:

Alan Little wrote:

Carved in mystic runes upon the very living rock, the last words of
Ambush Commander of comp.lang.php make plain:

It looks like in this particular case, $this->$x should be
sufficient.

Thanks, but no.

Otherwise, you may have to split up x into $x_object and $x_name
(exploding by -> should be sufficient) and calling
$x_object->$x_name. What you currently have, however, cannot be
done.

I'm not sure what you mean.
What I'm trying to do is parse variables
out of a string and substitute them with the value. $x (in this
example) would hold the variable name extracted from the string. I'm
trying to figure out how to get to the value of that variable, from
there.

That is exactly what it does.
$x = 'string'

$$x = $this->$x;
equals:
$string = $this->string;

$x is the variable name, $variable_name holds the value......

I don't get the problem?

What is the exact reason you're trying to accomplish? Maybe if you
elaborate some more, we get the picture. Why is it this doesn't
suffice?

For example:

$this->animal = 'lamb';
$this->string = 'Mary had a little {{animal}}';

The goal is to extract 'animal' from the string (no problem), convert it
to 'lamb' and replace it in the string (again, no problem). The question
is, if I have 'animal', how do I get 'lamb'? In global space, I would
simply have 'animal' in a variable, and use $$var to get 'lamb'.

So again, wouldn't this work:

$var = 'animal';
$this->$var; //this is translated to $this->animal, which in turn gives you
'lamb' .
--
"ohjelmoija on organismi joka muuttaa kofeiinia koodiksi" -lpk
sp**@outolempi.net | Gedoon-S @ IRCnet | rot13(xv***@bhgbyrzcv.arg)

[Alan Little]

Carved in mystic runes upon the very living rock, the last words of
Kimmo Laine of comp.lang.php make plain:

"Alan Little" <al**@n-o-s-p-a-m-phorm.com> wrote in message
news:Xn**************************@216.196.97.131.. .

Carved in mystic runes upon the very living rock, the last words of
Rik of comp.lang.php make plain:

Alan Little wrote:
Carved in mystic runes upon the very living rock, the last words of
Ambush Commander of comp.lang.php make plain:

> It looks like in this particular case, $this->$x should be
> sufficient.

Thanks, but no.

> Otherwise, you may have to split up x into $x_object and $x_name
> (exploding by -> should be sufficient) and calling
> $x_object->$x_name. What you currently have, however, cannot be
> done.

I'm not sure what you mean.
What I'm trying to do is parse variables
out of a string and substitute them with the value. $x (in this
example) would hold the variable name extracted from the string.
I'm trying to figure out how to get to the value of that variable,
from there.

That is exactly what it does.
$x = 'string'

$$x = $this->$x;
equals:
$string = $this->string;

$x is the variable name, $variable_name holds the value......

I don't get the problem?

What is the exact reason you're trying to accomplish? Maybe if you
elaborate some more, we get the picture. Why is it this doesn't
suffice?

For example:

$this->animal = 'lamb';
$this->string = 'Mary had a little {{animal}}';

The goal is to extract 'animal' from the string (no problem), convert
it to 'lamb' and replace it in the string (again, no problem). The
question is, if I have 'animal', how do I get 'lamb'? In global
space, I would simply have 'animal' in a variable, and use $$var to
get 'lamb'.

So again, wouldn't this work:

$var = 'animal';
$this->$var; //this is translated to $this->animal, which in turn
gives you 'lamb' .

Yes, that works; I just didn't understand what AB was saying.

--
Alan Little
Phorm PHP Form Processor
http://www.phorm.com/

[Dikkie Dik]

> For example:

$this->animal = 'lamb';
$this->string = 'Mary had a little {{animal}}';

The goal is to extract 'animal' from the string (no problem), convert it
to 'lamb' and replace it in the string (again, no problem). The question
is, if I have 'animal', how do I get 'lamb'? In global space, I would
simply have 'animal' in a variable, and use $$var to get 'lamb'.

Ah. Why not use str_replace?

And when you are using classes, you could as easily define a Variable
class with a Name and a Value method, and even a ToTemplate method that
puts the two pairs of curly braces around them.

If this is for a template engine, you probably have the name/value pairs
in a "named" array. In that case, a str_replace in a foreach loop does
the job just fine.

Best regards

[Alan Little]

Carved in mystic runes upon the very living rock, the last words of
Dikkie Dik of comp.lang.php make plain:

For example:

$this->animal = 'lamb';
$this->string = 'Mary had a little {{animal}}';

The goal is to extract 'animal' from the string (no problem), convert
it to 'lamb' and replace it in the string (again, no problem). The
question is, if I have 'animal', how do I get 'lamb'? In global
space, I would simply have 'animal' in a variable, and use $$var to
get 'lamb'.
Ah. Why not use str_replace?

The replacing part is not a problem.
And when you are using classes, you could as easily define a Variable
class with a Name and a Value method, and even a ToTemplate method
that puts the two pairs of curly braces around them.
I'm not sure I follow you here. I'm trying to get value names *from* a
string, and then get the values for those names.
If this is for a template engine, you probably have the name/value
pairs in a "named" array.

For some values, yes. But in other cases, such as error reporting, I need
to access an actual variable.

Anyway, I have it worked out now. But thank you for answering.

--
Alan Little
Phorm PHP Form Processor
http://www.phorm.com/