[RESOLVED] Assign object members to variables

phpSimon

Hi everyone

I have an array of stdClass objects.

At the moment it's non-trivial to change the structure of the array so I'm having to use what feels like a longhand way of getting all the contents of an object into the appropriate variable names.

foreach($clientarray AS $itemid => $objects){

if ($objects->ClientID == $_GET[clientid]){ //this one

    $ClientName = $objects->ClientName;
    $Contact = $objects->Contact;
    $Phone = $objects->Phone;
    $Fax = $objects->Fax;

     } // done assigning variable names to contents of correct object
} // done parsing array

Is there a more elegant way of:

1) Identifying which item in the array I want (rather than parsing the whole thing)? As I write this I realise I could exit the array parsing once I've found the specific object I want, which would save some looping, but jumping straight to it would be much better.

2) Assigning the variables. There are actually many more than the 4 shown; up to 20.

Long term I would have set the keys to the ClientID but for all sorts of reasons, I can't do that yet.
I would also prefer not to have the array contain stdObjects, but I didn't discover this solution on StackExchange until recently:

// These both give you an array:
$json = json_decode($whatever, true);
$json = (array) json_decode($whatever);

(credit to http://stackoverflow.com/questions/5515918/php-cannot-use-object-stdclass-as-array )

Thank you

Weedpacket

One thing I don't understand: why do you need all those variables? If there are so many and you need them all, why not keep them in the object? If you don't need them all why do you need to assign the rest anywhere?

If you really do need to assign all sorts of variables named after array indexes, [man]extract[/man] will do that. Of course, you'd be opening yourself up to problems if you can't predict what those variables will be called (because how would you ever find them?), so presumably you'd filter the array's keys to only include those you actually want.

Another thing: I don't understand what you mean by "Identifying which item in the array I want". Isn't that what $array['the_item_I_want'] does?

phpSimon

Thanks Weedpacket

I hadn't thought about leaving them in the object, good point. The reason for wanting to create them is partly habit, partly inexperience with objects and partly because I'm used to extracting variables from associative arrays in a single command.

I can't use $array['the_item_I_want'], it's not associative.

Array
(
    [0] => stdClass Object
        (
            [ClientID] => 1234
            [Contact] => Firstname Lastname    

            [Phone] => 01234 567890        

            [Fax] => 01234 567890                    

        )

[1] => stdClass Object
    (
        [ClientID] => 1234
        [Contact] => Firstname Lastname
        [Phone] => 01234 567890        
        [Fax] => 01234 567890                    
    )

[2] => stdClass Object
    (
        [ClientID] => 1234
        [Contact] => Firstname Lastname  
        [Phone] => 01234 567890        
        [Fax] => 01234 567890                    
    )
)

Derokorian

$array[0]; // where 0 is the numeric index of 'the_item_I_want' 🙂

NogDog

Another reason to just access them from the object (or array, as the case may be), is that it is then immediately apparent just from reading the code where the value came from, which can make maintenance easier 5 months or 2 years from now, at the mere expense of (perhaps) a wee bit more typing now.

phpSimon

Thanks again

Derokorian: In this case I need to identify the object by the ClientID contained within it; I don't know what the numeric index is.

NogDog: That's really good advice.

When I first started writing PHP I used to create variables for everything right at the top of every script; I felt that I knew where every variable had been set. Once my scripts started getting longer I got bored of scrolling up and down and started creating them all over the place; these days I'm more careful about how often I create them! Whenever I update old code, the first thing I find myself asking is 'what are all these variables doing, why do I have the same value in 10 different places and how long will it take me to sort them all out'.

I'm only now getting into OOP and this has been a pretty good primer on how to think about object values.

What's the proper terminology, anyway? Would you say an object contains keys and values, just like an array?

Derokorian

phpSimon;11024287 wrote:
Derokorian: In this case I need to identify the object by the ClientID contained within it; I don't know what the numeric index is.

Well, assuming your objects don't have repeating ClientID like your dummy data you showed, you could simply reindex it by ClientID. That could be pretty simple:

function ReindexByClientID(Array $array)
{
   $newArray = array();
   foreach( $array as $item )
   {
      $newArray[$item->ClientID] = $item;
   }
   return $newArray();
}

$array = json_decode($json);
$array = ReindexByClientID($array);

phpSimon;11024287 wrote:
Would you say an object contains keys and values, just like an array?

It can in a way if you consider properties as key/values but I wouldn't call them that. They are properties of the object. Which can be manipulated or used by methods in that object. Methods are definitely not key/values for an object, but functions specific to that class or instance of it.

phpSimon

I should have pointed out that the ClientID is unique! Thank for the elegant function, that's really helpful. I'll have a play with that.

Also thanks for the OOP help. I still don't have my head around it; more reading and experimenting to do!