how to append serial number to append fuction
$.ajax({
type: "GET",
url: "<?php echo base_url(); ?>bill/product_details",
data: {'product_id':product_id,'price':price},
complete: function(json){
re=json.responseText;
//alert(re);
var obj = jQuery.parseJSON(re);
//alert(obj[0].product_id+","+obj[0].price);
//var sl=0;
//var tmp=JSON.parse(re);
$('#main_pro').append('<tr class="trt" id="'+obj[0].product_id+"_"+obj[0].price+'" ><td class="sl">'+cnt+'</td><td class="name">'+obj[0].brand_name+obj[0].category_name+'</td><td><input type="text" style="width:60px;" class="sell_price" value="'+obj[0].price+'" /></td><td><input type="text" style="width:60px;" class="count_val" value="1" id="ct" onkeyup="find_total();test('+obj[0].product_id+','+obj[0].price+')" onkeypress="return isNumberKey(event)" /></td><input type="text" style="width:60px;" placeholder="Rate" title="Price" class="tb2 price_val" name=price[] onkeyup="find_total()" /></td><td ><input type="button" onclick="remove_product('+obj[0].product_id+','+obj[0].price+')" value="remove" /></td><input type="hidden" value="5" id="id_"/></tr>');
find_total();
}
});//ajax