Use a form with multiple checkboxes

If you want to use a form with multiple checkboxes (e.g. one per row) and assign the same name to each checkbox then the name needs to end with []. This tells PHP to put all checked values into an array variable.
For example:
<input type="checkbox" name="id[]" value="value_1">
<input type="checkbox" name="id[]" value="value_2">
..
<input type="checkbox" name="id[]" value="value_x">

You can now retrieve all values by using:
$values = $_POST['id'];

If the name does not end with [], then only a single value will be available via the $_POST variable even if the user checks several checkboxes.

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