Create class with class name

Question

I'm trying to figure a way to do create a class with only the class's name in PHP.

E.g.:

$class = "MyClass";

if(class_exists($class))
$unit = new $class($param1, $param2);
else
$unit = new Unit($param1, $param2);

Is there a way to do this in PHP? If possible, I'd also like to know if this is possible in Java.

Cheers! thanks in advance.

For java, see [this](http://stackoverflow.com/questions/1268817/create-new-class-from-a-variable-in-java). — Mac, Sep 10 '11 at 05:02
Also, for PHP see [this](http://stackoverflow.com/questions/1377052/can-php-instantiate-an-object-from-the-name-of-the-class-as-a-string). — Mac, Sep 10 '11 at 05:11

score 1 · Answer 1 · answered Sep 10 '11 at 05:03

1

I don't know about PHP (haven't used it in years), but in Java you can do:

MyClass obj = (MyClass) Class.forName("MyClass").newInstance( );

answered Sep 10 '11 at 05:03

Mac

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@willium: you've managed as fair a compromise as is possible, I think... (I assume the upvote was you) – Mac Sep 10 '11 at 05:15
it was. I could create a new question and allow you to answer, but that might be overkill. – willium Sep 10 '11 at 05:18
@willium: yep, definitely overkill. :) – Mac Sep 10 '11 at 05:20

score 0 · Answer 2 · answered Sep 10 '11 at 04:58

0

you can use double $ signs in PHP to make a variable well.. variable.

i.e.

$$class($param1,$param2);

I have not come across such a capability in Java.

Note: you probably don't want to call your class "class" as it is a reserved word ;)

answered Sep 10 '11 at 04:58

Ben

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score 0 · Accepted Answer · answered Sep 10 '11 at 05:04

Yep, it should work fine in PHP. I would write that like this in order to avoid duplicating all the parameters to the constructor (if they are the same, of course):

$class = 'MyClass';
if (! class_exists($class)) {
    $class = 'Unit';
}
$unit = new $class($param1, $param2);

Create class with class name

3 Answers3