Why can't these functions see my variable?

Question

Why do I get this error:

Undefined variable key_2captcha

I run this code to pass a CAPTCHA to 2captcha server:

<?php
$id_Captcha=0;
$key_2captcha="key2captcha";
function send_captcha($base_file){

   $ch = curl_init("http://2captcha.com/in.php");
   curl_setopt($ch, CURLOPT_POSTFIELDS,
               array('method'=>"base64",
                     'key'=>$key_2captcha,
                     'numeric'=>1,
                     'max_len'=>1,
                     'body'=>$base_file,
                     'submit'=>'download and get the ID'));


   curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);


   $postResult = curl_exec($ch);


   curl_close($ch);

   return $postResult;
}

function getSolveCaptcha($id_captcha){
  $c = curl_init("http://2captcha.com/res.php?key=".$key_2captcha."&action=get&id=".$id_captcha);
  curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
  $postResult = curl_exec($c);
  curl_close($c);
  return $postResult;
}
?>

I run this code in XAMPP.

Danilo Costa · Answer 1 · 2015-04-01T15:52:21.313

I thinks you have a variabile scope resolution problem.

If you want to use the variable into a generic function, you have to pass this variable as parameter in the signature of function. Not use variable as global because is a bad practice, you have to make generic function so you have to use generic parameter.

Try this code:

<?php
$id_Captcha=0;
$key_2captcha="key2captcha";
function send_captcha($base_file, $key_2captcha){

   $ch = curl_init("http://2captcha.com/in.php");
   curl_setopt($ch, CURLOPT_POSTFIELDS,
               array('method'=>"base64",
                     'key'=>$key_2captcha,
                     'numeric'=>1,
                     'max_len'=>1,
                     'body'=>$base_file,
                     'submit'=>'download and get the ID'));


   curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);


   $postResult = curl_exec($ch);


   curl_close($ch);

   return $postResult;
}

function getSolveCaptcha($id_captcha, $key_2captcha){
  $c = curl_init("http://2captcha.com/res.php?key=".$key_2captcha."&action=get&id=".$id_captcha);
  curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
  $postResult = curl_exec($c);
  curl_close($c);
  return $postResult;
}

//Call Example
send_captcha($base_file, $key_2captcha);
?>

I expect you'd need a `$key_2captcha` parameter for the second function too? — halfer, Apr 01 '15 at 09:26
Yeah, i'll edit my answer for that! You need the parameter for each function where you will use it. — Danilo Costa, Apr 01 '15 at 15:51

score -1 · Accepted Answer · answered Apr 01 '15 at 07:58

-1

Use below code use $key_2captcha with global. in both function. read variable scope in PHP

function getSolveCaptcha($id_captcha){
  global $key_2captcha;

  $c = curl_init("http://2captcha.com/res.php?key=".$key_2captcha."&action=get&id=".$id_captcha);
  curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
  $postResult = curl_exec($c);
  curl_close($c);
  return $postResult;
}

answered Apr 01 '15 at 07:58

Nishit Maheta

6,021
3
17
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It's worth pointing out, of course, that `global` variables are nearly always the wrong solution. Keeping track of what you can use, and ensuring you don't corrupt global state, can be complicated. – halfer Apr 01 '15 at 16:00

score -1 · Answer 3 · answered Apr 01 '15 at 08:00

Use below code with $GLOBALS — References all variables available in global scope

<?php
    $id_Captcha=0;
    $key_2captcha="key2captcha";
    function send_captcha($base_file){

       $ch = curl_init("http://2captcha.com/in.php");
       curl_setopt($ch, CURLOPT_POSTFIELDS,
                   array('method'=>"base64",
                         'key'=>$GLOBALS['key_2captcha'],
                         'numeric'=>1,
                         'max_len'=>1,
                         'body'=>$base_file,
                         'submit'=>'download and get the ID'));


       curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);


       $postResult = curl_exec($ch);


       curl_close($ch);

       return $postResult;
    }

    function getSolveCaptcha($id_captcha){
      $c = curl_init("http://2captcha.com/res.php?key=".$GLOBALS['key_2captcha']."&action=get&id=".$id_captcha);
      curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
      $postResult = curl_exec($c);
      curl_close($c);
      return $postResult;
    }
    ?>

Ref PHP.net

Why can't these functions see my variable?

3 Answers3