ASP.NET

string cookie = "LotID1=7&LotNo1=003462&LotName1=Lot 7&BuyPrice1=850&StockQuantity1=56&LotID2=5&LotNo2=003859&LotName2=Lot 3&BuyPrice2=154&StockQuantity2=2";

string[] values = cookie.Split('&');

string[] newValues = (from cv in values
			let eqIdx = cv.IndexOf('=')
			let name = cv.Substring(0, eqIdx)
			let value = cv.Substring(eqIdx + 1)
			where name != "LotName2"
			select cv).ToArray();

string newCookie = String.Join("&", newValues);

if (Request.Cookies["MyCookie"] != null)
{
    HttpCookie myCookie = new HttpCookie("MyCookie");
    myCookie.Expires = DateTime.Now.AddDays(-1d);
    Response.Cookies.Add(myCookie);
}

<script type="text/javascript">
<!--
  	deleteCookie('MyCookie');
// -->
</script>