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eval in eval

bitfactory
bitfactory asked
on
Medium Priority
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Last Modified: 2010-05-18
Hi All,
I'm having a issue with evel() in PHP. I have a class, which has a function DoAction. This function shall use eval() in order to run some objects function according to what action was set while object was constructed. Here's how I'm doing it now and how it works:

 private function DoAction()
 {
       echo("DoAction: <br/>");
       eval("\$val = \$this->Action();");
       eval("\$this->$val();");
 }

However I was wondering if it is possible to put it in one eval. I was trying something like:

 private function DoAction()
 {
       echo("DoAction: <br/>");
       eval("\$val = \$this->Action();");
       eval("\$this->eval(\"return \$this->Action();\");");
 }

but this thins (logically) that the eval() inside the eval() is the objects function, which is not defined ...

Is there a way how to make this or shall I use that two eval() solution?

Thanks
Comment
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Commented:
if i am not wrong u want to achive some thing bellow

 private function DoAction()
 {
      echo("DoAction: <br/>");
      eval("return \$val=\$this->Action();\");
 }
 or if u don't want to store it in $val then u can use the following

 private function DoAction()
 {
      echo("DoAction: <br/>");
      eval("return \$this->Action();\");
 }

Author

Commented:
Hi,
maybe I didn't tell it clearly. The thing you wrote will return only a action string. the function $this->Action() returns a string which is a name of the function to be executed.

So in fact i want to call the function which name is returned by $this->Action();

e.g. $this->Action returns "test" so I want to call function $this->test();

the thig you wrote only returns the string "test" and doesn't call the function ...

Top Expert 2007
Commented:
ever thought of using reflection ( http://de3.php.net/reflection ) for that kind or http://de3.php.net/manual/en/function.call-user-func.php

e.g.
private function DoAction()
 {
      echo("DoAction: <br/>");
      $val = $this->Action();
      call_user_func(array($this, $val));
 }

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Author

Commented:
thanks hernst42 i'll check out the reflections... Didn't know of them before. I accept your answer as it was helpful.

Commented:
sorry i am late
but i found an answer

try this out

private function DoAction()
{  
    echo("DoAction: <br/>");
    @eval("\$val=\$this->".eval('return \$this->Action();')."();");
    return $val;
}

Author

Commented:
Thanks anilande:) This would have worked as well :) But now I'm using call_user_func instead which looks more elegant.
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