access a property via string with array in php?

Question

I have a big list of properties that I need to map between two objects, and in one, the value that I need to map is buried inside an array. I'm hoping to avoid hard-coding the property names in the code.

If I have a class like this:

class Product {
    public $colors, $sizes;
}

I can access the properties like this:

$props = array('colors', 'sizes');
foreach ($props as $p) {
    $this->$p = $other_object->$p;
}

As far as I can tell, if each of the properties on the left are an array, I can't do this:

foreach ($props as $p) {
    $this->$p[0]['value'] = $other_object->$p;
}

Is that correct, or am I missing some clever way around this?

(This is in drupal, but I don't really think that matters.)

awgy · Accepted Answer · 2010-05-11 23:10:59Z

4

I believe you can wrap it in curly braces {}:

foreach ($props as $p) {
    $this->{$p}[0]['value'] = $other_object->$p;
}

Edit:

Okay. Now my brain turned on. Sorry for the confusing edits.

answered May 11, 2010 at 23:10

awgy

17k4 gold badges28 silver badges18 bronze badges

Sign up to request clarification or add additional context in comments.

1 Comment

mike clagg Over a year ago

this is the proper technique to dynamically set object properties

mike clagg · Accepted Answer · 2010-05-11 23:17:16Z

1

Also try this:


$props = get_object_vars($this);

answered May 11, 2010 at 23:17

mike clagg

8407 silver badges12 bronze badges

Comments

Mark Tomlin · Accepted Answer · 2010-05-12 00:45:21Z

0

foreach ($props as $p) {
    $this->{$p}[0]['value'] = $other_object->{$p};
}

It's called variable, variables.

edited May 12, 2010 at 0:45

answered May 11, 2010 at 23:19

Mark Tomlin

8,97311 gold badges60 silver badges74 bronze badges

2 Comments

awgy Over a year ago

$p on the first go-round would be 'colors'. $$p would try to access $colors to use as the property name, which is not desired here, since $colors is not a defined variable. Remove the extra $ in $$p and you're good.

Mark Tomlin Over a year ago

Thank you @awgy. Credit should really go to you for this one then.

Artefacto · Accepted Answer · 2010-05-11 23:10:46Z

-1

I don't understand your problem. This works:

class Test {
    public $prop = "prov value";
}
$arr = array(array("prop"));
$test = new Test();
$test->$arr[0][0] = "new prop value";
var_dump($test);

result:

object(Test)#1 (1) {
  ["prop"]=>
  string(14) "new prop value"
}

answered May 11, 2010 at 23:10

Artefacto

98.1k17 gold badges207 silver badges230 bronze badges

1 Comment

sprugman Over a year ago

Your example doesn't do what I need. You're setting $test->prop to a value; In my case, $test->prop itself is an array, and I need to set a portion of that. The curly braces above work.

Collectives™ on Stack Overflow

access a property via string with array in php?

4 Answers 4

1 Comment

Comments

2 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

4 Answers 4

1 Comment

Comments

2 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related