将多个表单输入名称循环到数组

I have a form like this:

</span><select data-role=slider name="ndata[0]" /><option value=0> E </option><option value=1> F </option></select>
  <span>1b: </span><select data-role=slider name="ndata[1]" /><option value=0> E </option><option value=1> F </option></select>
  <span>1c: </span><select data-role=slider name="ndata[2]" /><option value=0> E </option><option value=1> F </option></select>

Then, I want to insert every data to a looping process in php file. This is my script:

<?php
foreach( $_GET['ndata'] as $ch => $data ) {
    $flag = 0;
       if($data[$flag] == 0){
          echo "<li><a href=\"img2.php\" target=\"blank\">Sektor ".($flag + 1)."</a></li>
";}
    $flag++;}
?>

I've tried that and I get some errors. Do you have any idea?

I assume, you want to print something like that if "E" is selected.

Sektor 1
Sektor 2

if so you should use this code segment:

foreach( $_GET['ndata'] as $key => $value ) {
   if($value == 0) {
       echo "<li><a href=\"img2.php\" target=\"blank\">Sektor ".($key + 1)."</a></li>
";
   }
}

because, $_GET['ndata'] will return such array:

array(3) { 
           [0]=> string(1) "0"
           [1]=> string(1) "1" 
           [2]=> string(1) "0" 
         }

so above code segment helps you to print correct sector number ($key + 1) by looking $value .

if this is not the case, can you write errors you got in detail.