What does $this refer to in a Model?

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What does $this refer to in a Model? - dangyuluo - 01-28-2016

When initialising a model(such as a class called Mall), I can pass a TRUE in the third parameter to automatically connect to the default database. Then a member named mall is assigned to CI_Controller and I can use $this->mall->foo() to use the function defined in the Model.
And I notice that, in the Loader:database(), the 'db' variable is assigned to $CI, which is the CI_Controller super object.

But here comes the question:
In the model I can still use $this->db-> to get access to DB handler. Does that means that "$this" in a Model refers to CI_Controller? If so, where can I find the detailed definition?

Thanks.

RE: What does $this refer to in a Model? - Narf - 01-28-2016

No, $this always refers to the instance of the class you are currently in.

You can access controller properties because of a magic __get() method: https://github.com/bcit-ci/CodeIgniter/blob/3.0.4/system/core/Model.php#L71

RE: What does $this refer to in a Model? - dangyuluo - 01-28-2016

(01-28-2016, 10:31 AM)Narf Wrote: No, $this always refers to the instance of the class you are currently in.

You can access controller properties because of a magic __get() method: https://github.com/bcit-ci/CodeIgniter/blob/3.0.4/system/core/Model.php#L71

I know that $this refers to the most direct class, but how to explain that in a Model, $this can call the function or variable of CI_Controller?

RE: What does $this refer to in a Model? - Narf - 01-29-2016

By actually reading my second sentence and those links? Smile

RE: What does $this refer to in a Model? - dangyuluo - 01-29-2016

(01-29-2016, 02:06 AM)Narf Wrote: By actually reading my second sentence and those links?

I'm not trying to offend you, but maybe you misunderstand my question.
I can surely use _get to get access to function and variable of CI_Controller. I have known that quite before.
But my question actually is, since I have experimented before, why can I use $this->cache->redis in a model, in which $this should refer to the Model Class, not the CI_Controller?

RE: What does $this refer to in a Model? - Narf - 01-29-2016

(01-29-2016, 03:06 AM)dangyuluo Wrote:
(01-29-2016, 02:06 AM)Narf Wrote: By actually reading my second sentence and those links?

I'm not trying to offend you, but maybe you misunderstand my question.
I can surely use _get to get access to function and variable of CI_Controller. I have known that quite before.
But my question actually is, since I have experimented before, why can I use $this->cache->redis in a model, in which $this should refer to the Model Class, not the CI_Controller?

No offense taken, but you're contradicting yourself ...

If you knew how __get() works (that's two underscores, not one), then you wouldn't be asking this question. And if you don't understand it - you didn't really follow through that first link, which explains it:

Code:
$this->cache

Is interpreted by PHP (given the current state of your class) as:

Code:
[current class instance] -> [inaccessible or non-existent property]

And gets executed as:

Code:
[current class instance] -> __get([name of the inaccessible or non-existent property])

That's what __get() is made for, you don't use it as $this->__get($something) ... that'd be silly.

RE: What does $this refer to in a Model? - LeMec - 01-29-2016

(01-29-2016, 03:41 AM)Narf Wrote:
(01-29-2016, 03:06 AM)dangyuluo Wrote:
(01-29-2016, 02:06 AM)Narf Wrote: By actually reading my second sentence and those links?

I'm not trying to offend you, but maybe you misunderstand my question.
I can surely use _get to get access to function and variable of CI_Controller. I have known that quite before.
But my question actually is, since I have experimented before, why can I use $this->cache->redis in a model, in which $this should refer to the Model Class, not the CI_Controller?

No offense taken, but you're contradicting yourself ...

If you knew how __get() works (that's two underscores, not one), then you wouldn't be asking this question. And if you don't understand it - you didn't really follow through that first link, which explains it:

Code:
$this->cache

Is interpreted by PHP (given the current state of your class) as:

Code:
[current class instance] -> [inaccessible or non-existent property]

And gets executed as:

Code:
[current class instance] -> __get([name of the inaccessible or non-existent property])

That's what __get() is made for, you don't use it as $this->__get($something) ... that'd be silly.

When my grand kids ask me: Grampa! What did you really accomplish in your life?

I will answer: Well I had a huge impact on the CodeIgniter community by making one of the most knowledgeable person on that site become a lot more patient Tongue

RE: What does $this refer to in a Model? - Narf - 01-29-2016

(01-29-2016, 11:32 AM)LeMec Wrote: When my grand kids ask me: Grampa! What did you really accomplish in your life?

I will answer: Well I had a huge impact on the CodeIgniter community by making one of the most knowledgeable person on that site become a lot more patient

So typical of ancestors, to over-value themselves in front of the little kids. Smile

Seriously, don't flatter yourself. I didn't suddently become any more patient and at this rate, the only thing you're accomplishing is making foes.

RE: What does $this refer to in a Model? - LeMec - 01-29-2016

(01-29-2016, 12:45 PM)Narf Wrote:
(01-29-2016, 11:32 AM)LeMec Wrote: When my grand kids ask me: Grampa! What did you really accomplish in your life?

I will answer: Well I had a huge impact on the CodeIgniter community by making one of the most knowledgeable person on that site become a lot more patient

So typical of ancestors, to over-value themselves in front of the little kids.

Seriously, don't flatter yourself. I didn't suddently become any more patient and at this rate, the only thing you're accomplishing is making foes.

That's ok...I am making new friends now...somewhere else Big Grin

RE: What does $this refer to in a Model? - skunkbad - 01-29-2016

(01-29-2016, 11:32 AM)LeMec Wrote:
(01-29-2016, 03:41 AM)Narf Wrote:
(01-29-2016, 03:06 AM)dangyuluo Wrote:
(01-29-2016, 02:06 AM)Narf Wrote: By actually reading my second sentence and those links?

I'm not trying to offend you, but maybe you misunderstand my question.
I can surely use _get to get access to function and variable of CI_Controller. I have known that quite before.
But my question actually is, since I have experimented before, why can I use $this->cache->redis in a model, in which $this should refer to the Model Class, not the CI_Controller?

No offense taken, but you're contradicting yourself ...

If you knew how __get() works (that's two underscores, not one), then you wouldn't be asking this question. And if you don't understand it - you didn't really follow through that first link, which explains it:

Code:
$this->cache

Is interpreted by PHP (given the current state of your class) as:

Code:
[current class instance] -> [inaccessible or non-existent property]

And gets executed as:

Code:
[current class instance] -> __get([name of the inaccessible or non-existent property])

That's what __get() is made for, you don't use it as $this->__get($something) ... that'd be silly.

When my grand kids ask me: Grampa! What did you really accomplish in your life?

I will answer: Well I had a huge impact on the CodeIgniter community by making one of the most knowledgeable person on that site become a lot more patient

LeMec, I don't understand why you would post such a thing. Here is Narf trying to help somebody, and you are like a heckler, a court jester, or maybe just a modern forum troll. The last thread I watched you basically hijack was all about your personal grudge against Narf and his lack of explaining things to your satisfaction. In the end, the OP was satisfied, and he/she seemed confused or amused about your rant than anything else. It's pretty rude to hijack threads, and I don't have any moderation powers here, but if I did I'd be scolding you right now.