Solved

eval in eval

Posted on 2006-10-25
6
531 Views
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
0
Comment
Question by:bitfactory
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6 Comments
 
LVL 4

Expert Comment

by:anilande
ID: 17809819
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();\");
 }
0
 

Author Comment

by:bitfactory
ID: 17809917
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 ...

0
 
LVL 48

Accepted Solution

by:
hernst42 earned 50 total points
ID: 17810025
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));
 }
0
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Author Comment

by:bitfactory
ID: 17810218
thanks hernst42 i'll check out the reflections... Didn't know of them before. I accept your answer as it was helpful.
0
 
LVL 4

Expert Comment

by:anilande
ID: 17810347
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;
}
0
 

Author Comment

by:bitfactory
ID: 17810387
Thanks anilande:) This would have worked as well :) But now I'm using call_user_func instead which looks more elegant.
0

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