question about eval

[chronister]

Hello, I am trying to "evaluate" code passed through an array.

 

basically it looks like this...

 

$data = array('dependsOn'=>'name == bob');

 

I want to be able to take the name == bob part of the array and actually use that part in an expression.

 

I used explode to break it apart, but the only way I can figure out how to determine the operator is to use a switch statement to check it over. Is there a way to take it and use it inside the var??

 

e.g.

<?php
$parts = explode(' ', $v['dependsOn']);
if($_POST[$parts[0]]. $parts[1]. $parts[2]){
echo 'true';
}
?>

to turn it into

 

<?php
if($_POST['name'] == 'bob') {
  //do something here because it is true.
}
?>

 

eval does not seem to work here as the string passed to eval should have the entire if statement inside it, and it appears that a == inside a var will not be used as an operand.

 

What would be the best way to do this kind of thing?

 

Thanks in advance.

 

nate

[wrs]

The problem here is that your eval() statement must be sane PHP.

 

eval('if ($user == "something") return true; else return false;')

 

Now your eval statement will return true or false, and can be placed within your if() block.

 

$o = 'name == bob';

	$parts = explode(' ', $o);

	$user = Array(
		'name' => 'bob',
	);

	$str = 'if ($user[\''.$parts[0].'\'] '.$parts[1].' \''.$parts[2].'\') return true; else return false;';

	if (eval($str))
		echo 'name matches';
	else
		echo 'name does not match';