php multiple checkbox array not working

I am currently struggling with a very basic part of a PHP form. I've created a form with a single checkboxes, each assigned a different database Ids value, I want these to be sent to a variable (array?) for deleting a records from database.

but problem is that when i checked multiple check box form only posting single value and single record via using jquery ajax post and php function deleted only single record?

and second thing i want add to parents fade out option after single/multiple records delete from database after ajax success?

I've looked around for a few examples here but a lot of them but i can't get solution for my problem.

Here Html

<form name="update_products_form" class="update_products_form"  
id="myForm" action="?ToDo=runAddon&addon=<?php echo $this->name; ?  
>&actionMode&mdelete" method="post" /> 

<input type="checkbox" class="update_record_checkbox"
name="selected_records[<?=$item['id']?>]" id="checkbox_<?=$item['id']?>"
title="Update this record" value="<?=$item['id']?>" />   

</form>

 <div class="toggle">

 <span class="option">
 <a href="#" role="button" class="toggleBtn" title="Delete">
 <input type="button" class="buttonsupp" id="delsupplier"  value="Delete Suppliers" >
 </a>
 </span>

 <span  class="update_message"></span>

 <div class="link">
 <?php echo $name ?>
 <?php echo $class ?>
 <?php echo $subject ?>
 </div> 


 </div>

Here Ajax

// Toggle the delete buttons

$(".toggleBtn").click(function(e){
    var remove = $(this).parent().filter(".option"),
        show = remove.hide().siblings().show();

    e.preventDefault();
});


$("#delsupplier").click(function()
{   

if(CheckedCkeckBoxes('update_record_checkbox')  ==  0){
    alert('Please select atleast one record.');
return false;
} 

var action = $('.update_products_form').attr('action');
var parent = $(this).parents(".link");

   $.ajax({
   type: "POST",
   url: action,
   data: $("#myForm").serialize(),

   success: function(msg){
   $('span.update_message').html('supplier deleted successfully.');

   parent.effect("highlight",{color:"#fb6c6c"},500).fadeOut(200,function(){ 
   //function not working after deleted single record
   parent.remove();//function not working after deleted single record

   },
   error: function(){
   $('span.update_message').html('Something went wrong, Please try again.');
   }

});

    return false;


});

Here Php Code

if(isset($_REQUEST['mdelete'])){

        $record_ids = array();
        foreach($_POST['selected_records'] as $id => $email)
        {
        $record_ids[]= "'$id'";
        }
        $record_ids = implode(',', $record_ids);
        $sql = "DELETE FROM [|PREFIX|]order_custom_payment_vendors WHERE id IN($record_ids) ";
}