remember checkbox value if its checked array name in a form php

Question

lets say we have this:

echo '<form method="post">
        <div class="form-group">
            <table class="table table-bordered table-hover table-striped" style="width:auto">
              <tr>
                <td><label for="array">ARRAY_NAME</label></td>        
                <td>
                 <input type="checkbox" name="array[]" value="1" /> option1<br />
                 <input type="checkbox" name="array[]" value="2" /> option2
                </td>
              </tr>
              <tr>
                <td><label for="array2">ARRAY_NAME2</label></td>        
                <td>
                 <input type="checkbox" name="array2[]" value="1" /> option1<br />
                 <input type="checkbox" name="array2[]" value="2" /> option2
                </td>
              </tr>
              <tr>
                <td><label for="array3">ARRAY_NAME3</label></td>        
                <td>
                 <input type="checkbox" name="array3[]" value="1" /> option1<br />
                 <input type="checkbox" name="array3[]" value="2" /> option2
                </td>
              </tr>
           </table>
        </div>
        <button type="submit" name="submit" class="btn btn-success">Submit</button>
</form>';

I tried to implement this code: <?php echo (isset($_POST['array1[0]']) && $_POST['array1[0]'] == 1) ? "checked='checked'" : "" ?>

but it didn't work! It only works if you have name="array1" and name="array2". this way I'm thinking I can save multiple data in a parent array saved! Like this form[array1[],array2[],array3[]].

Can someone give me a solution because I'm stuck! Thanks in advance guys!!

Answer 1

You are trying to access the values incorrectly.

You can access a array posted like this:

echo $_POST['array1'][0];

php.net/$_POST See the first comment.

Answer 2

When you put square brackets in the name of form control, PHP will inflate that set of elements with similar names into an array.

You need to access:

$_POST['array1'][0]

not

$_POST['array1[0]'] // This is incorrect

(You also need to match the actual name of your control: Your HTML has array, array2 and array3 but not array1)