PHP - getting key and value using checkbox

Question

    Documents     Original            Xerox
-------------------------------------------------
    ABC          <checkbox>          <checkbox>
    DEF          <checkbox>          <checkbox>
    XYZ          <checkbox>          <checkbox>

I have a checkbox structure, as you see it above. But I am not sure, how am I suppose to implement it. I know the working of a normal checkbox, as it has only one checkbox. But in this case, for every document, there are 2 checkbox (original copy and xerox copy)

What I have in mind like, after the submit is clicked, I need to somehow get an array in a form like below

ABC -> [1][1]
DEF -> [0][1]
XYZ -> [1][0]

Where first [] is orginal, and second [] is xerox. Where 1 denotes that it was checked, and 0 denotes unchecked.

I am not getting an idea how should I implement it. This is my code...(It may be horribly wrong, i agree.. but i still i made an attempt.. but couldn't figure it out.)

<table>
  <tr>
  <td>Aadhar</td>
  <td><input type="checkbox" name="document[]" value="1"/></td>
  </tr>
  <tr>
  <td>Pan Card</td>
  <td><input type="checkbox" name="document[]" value="1"/></td>
  </tr>
  <tr>
  <td>Address</td>
  <td><input type="checkbox" name="document[]" value="1"/></td>
  </tr>
  <tr>
  <td>Light Bill</td>
  <td><input type="checkbox" name="document[]" value="1"/></td>
  </tr>
  <tr>
  <td><input type="submit" value="Submit" /></td>
  </tr>
</table>

PHP

$documents = $_POST['document'];
$a = implode($documents);
echo $a;

So far, I am getting 1 (value) correctly.. But I also need the document (key) to which the '1'(value) belongs. Can anyone help me out please.

Answer 1

Checkboxes only submit WHEN CHECKED, so you'll NEVER get a checkbox submitting a "0" value.

That said, you can know it's NOT checked by simply asking PHP if it was set, like so: isset($_POST['document']['aadhar'][1]) -- if that returns true, it was checked, if not, it was not checked.

One thing to note: You're going to want to specify indexes for your second dimension of the array, so this:

<td><input type="checkbox" name="document[aadhar][]" value="1"/></td>

Becomes this:

<td><input type="checkbox" name="document[aadhar][original]" value="1"/></td>

That way you can track the "column" of which checkbox was selected by asking isset().

Here is a working example: http://myingling.com/random/random/44476276/

Here is the HTML from that example:

<form action='post.php' method='post'>
   <table>
     <tr>
      <td>Aadhar</td>
      <td><input type="checkbox" name="document[aadhar][col1]" value="1"/></td>
      <td><input type="checkbox" name="document[aadhar][col2]" value="1"/></td>
    </tr>
    <tr>
      <td>Address</td>
      <td><input type="checkbox" name="document[light][col1]" value="1"/></td>
      <td><input type="checkbox" name="document[light][col2]" value="1"/></td>
    </tr>
    <tr>
      <td><input type="submit" value="Submit" /></td>
    </tr>
  </table>
</form>

Here is the PHP from the post.php:

<?php
echo "<pre>";
var_dump($_POST);
echo "</pre>";