Passing a value through Button to Php function

You can do it one of two ways.

jQuery and AJAX

For each <tr>, everywhere there is a delete button,

<a href="#" data-id="<?php echo $value; ?>" class="delete-row">Delete</a>

Script at the bottom:

//Include jQuery here
<script language="javascript">
$('.delete-row').click(function (event) {
   event.preventDefault();
   var id = $(this).data('id');
   $.ajax({
      url: "url/to/delete",
      method: "POST",
      cache: false,
      data: { id: id },
      success: function (html) {
         $(this).parent().parent().remove();
      });
   });
});
</script>

This puts the ID of the row into the <a href> itself using data and uses jQuery to send out an AJAX call to delete the record. If the delete is successful, it removes the row from the table.

Old-School Button

For each <tr>, everywhere there is a Delete button,

<form method="POST" action="url/to/delete">
<input type="hidden" name="id" value="<?php echo $value; ?>" />
<input type="submit" value="Delete" />
</form>

This is the old-school way to do it, where the hidden field is how the backend knows which row to delete.

On the backend, you still use $_POST['id']; to get the ID of the record to remove. In the above examples, $value is the ID for each row, and is most likely something like $row['id'] when it is coming from a foreach().

Use a hidden input (e.g.<input type="hidden" value="your_value_here">)

when you click Edit it open a page with corresponding record. You can do it by a Edit link or a image or a button.

<?php echo "<a href='".BASE_URL."admin/edit.php?id=$id' target='_blank'> <img src=".BASE_URL."/images/edit.png width=16 height=16 alt=Edit /> </a>";?>

for delete you can use jquery. here is a example

echo "<a href='#' onclick='deletePrescription($id)' ><img src=images/document_delete.png width=16 height=16 title='Delete Prescription' alt=Delete /> </a>";    
<script type="text/javascript">
function deletePrescription(checkup_id) {
//alert(checkup_id);                
var agree=confirm("Do you really want to delete the prescription?");
    if (agree)
        {
            $.ajax
            ({
                type: "POST",
                url: "delete_prescription_admin.php",
                data: "checkup_id="+checkup_id,
                success: function(msg)
                {
                //
                //alert( "array Updated: " + msg );
                location.reload(true);
                }
            });

        }
    else
        {
        return false ;
        }

      }
     </script> 

PHP is on the server side, so you need to send parameters, parse it and have your php act. i.e.

The edit button will make POST or GET request with parameter: id=123&action=edit

and your PHP will parse the Query String:

$strID = $_GET['id'];
$strAction = $_GET['action'];

then act on it..

if ($strAction=='edit'){
 // do something...
}

Your buttons should be wrappen in a form like:

<form action="yourFile.php?id=<?=$SN ?>&action=edit" method="GET" id="formEdit<?=$SN ?>">
    <button type="submit" value="Edit">
</form>

<a href=register_course.php?id=$roll&code=".$row['course_code']."&name=".$row['course_name']."><input type=submit value=Register>

*here register_course.php is the file where you are sending some variable having some data it will be delivered when button is clicked whose value is register //course code is the variable you want to send ... im assigning its value as $ code... and assigning id $roll as id and assigning course_name as $name....

the other file will get the variables having some data