Question

I have a checkbox group in one form that I need to be posted.

<input type="checkbox" value="true" checked name="chk0[]">
<input type="checkbox" value="false" name="chk0[]">
<input type="checkbox" value="false" name="chk0[]">
<input type="checkbox" value="true" checked name="chk0[]">

<input type="checkbox" value="true" checked name="chk1[]">
<input type="checkbox" value="false" name="chk1[]">
<input type="checkbox" value="true" checked name="chk1[]">
<input type="checkbox" value="false" name="chk1[]">

Note that in the first group, 1 and 4 are checked. In the second group, 1 and 3 are checked.
When I post this, I get the posted values for the checked checkboxes sequentially as under:

[chk0] => Array ( 
          [0] => true 
          [1] => true 
        ) 
[chk1] => Array ( 
          [0] => true 
          [1] => true 
        ) 

How can I make sure I get the posted values like this:

[chk0] => Array ( 
          [0] => true 
          [3] => true 
        ) 
[chk1] => Array ( 
          [0] => true 
          [2] => true 
        ) 

I wanted to know the keys of the checked checkboxes instead of showing me sequentially.

Thanks

Answer 1

<input type="checkbox" value="true" checked name="chk0[0]">
<input type="checkbox" value="false" name="chk0[1]">
<input type="checkbox" value="false" name="chk0[2]">
<input type="checkbox" value="true" checked name="chk0[3]">

<input type="checkbox" value="true" checked name="chk1[0]">
<input type="checkbox" value="false" name="chk1[1]">
<input type="checkbox" value="true" checked name="chk1[2]">
<input type="checkbox" value="false" name="chk1[3]">

See what I mean?
The <input name="chk0[1]" ...> boxes work just like array elements inside PHP. You can specify the indexes an they will be transfered as-is into PHP as $_POST['chk0'][1] elements.