Evaluate Variable as code

[tkdasearls]

Is there a way to evaluate a php variable as code instead of a string?  

$sql1 = mysql_query("SELECT * FROM form WHERE id='".$id."'");
while($row1 = mysql_fetch_array($sql1)){
$id1 =$row1["id"];
$name1 =$row1["name"];
$name1 = str_replace(' ', '', $name1);
$name1 = str_replace('-', '', $name1);
$errorline .= "".$_POST[$name1]."=='' || ";
}

	

$errors = "if(".$errorline."){";
$errors .= '$error=1}';
eval($errors); 
echo $error;

I am able to make $errors look the way I want it to.:

if(=='' || =='' || =='' || =='' || =='' || =='' || =='' || =='' || =='' || =='' || =='' || =='' || ){$error=1}

 

Where before the "==" is a post variable, thats why its not showing.  I need to know how I can change this to code instead of a variable.  As you can see, I tried the "eval" function, but it gives a T_IS_EQUAL error.

 

Can anyone help?  If I have to change my logic I will, but I think you probably get the point as to what I am trying to achieve.  This is for error checking of a dynamically created form.

[tkdasearls]

I realized where my error is at.  it is returning a blank for "$_POST[$name1] when I actually need it to return $_POST[$name1].  How do I make it do this?  I tried putting this part inside of quotes, but it is still returning blank and not the actual term "$_POST[$name1]".  How do I make it do this?

[tkdasearls]

got it.  didn't realize there was a difference between ' and "

[gizmola]

This is what functions are for.  

 

Trying to make a giant if statement and then eval it is a really bad idea.  Heck using eval at all is something to be avoided.

 

Just to get an idea of something that has actually been thought out, take a look at the symfony2 validation component:  http://symfony.com/doc/current/book/validation.html

 

 

With that said you could also just write something simple like:

 

 

<?php
 
function checkForNull($rows) {
    // return array of errors
    $errors = array();
    foreach($rows as $row) {
        $name1 =$row["name"];
        $name1 = str_replace(' ', '', $name1);
        $name1 = str_replace('-', '', $name1);
        if ($_POST[$name1] == '') {
            $errors[] = $name;
        }
    }
    return $errors;
}
 
 
$sql1 = mysql_query("SELECT * FROM form WHERE id='".$id."'");
$rows = array();
while ($rows[] = mysql_fetch_assoc($sql1)) {
  // Fetch all  rows  
}
 
$errors = checkForNulls($rows);
 
if (count($errors) > 0) {
    // You can cycle through this to figure out all the null POST fields and display an error or annotate the form
}