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 protected void btnAddToCart_Click(object sender, EventArgs e)
        {
            //lblMessage.Text = "Hi";
            //Response.Write("<script>alert('Hi');</script>");

            if (Session["CustomerID"] == null)
            {
                //lblMessage.CssClass = "alert alert-danger";
                //lblMessage.Text = "Please Login first then add products!";
                ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "SweetAlert", "swal('Oops!', 'Please Login first then add products!', 'warning');", true);

                Response.Redirect("~/Login");
                return;
            }

            Int64 _selectedPID = Convert.ToInt64((sender as Button).CommandArgument);

            _CustomerID = Session["CustomerID"].ToString();
            Int64 Id = 0;
            string _action = "INSERT";
            foreach (DataListItem items in this.DataList1.Items)
            {
                Int64 _productId = Convert.ToInt64((items.FindControl("Lbl_ProductID") as Label).Text);
                string _productName = (items.FindControl("LblProudctName") as Label).Text;
                string _productPrice = (items.FindControl("lblproductPrice") as Label).Text;
                TextBox txtQt = (items.FindControl("txtQuantity") as TextBox);

                Int64 _userQty = Convert.ToInt64(txtQt.Text);
                int _stockQty = Convert.ToInt32((items.FindControl("lblStockQty") as Label).Text);

                if (_stockQty < _userQty)
                {
                    //lblMessage.Text = "Enter qty of less than " + _stockQty.ToString();
                    ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "SweetAlert", "swal('Enter Qty Less than " + _stockQty.ToString() + "');", true);
                    return;
                }

                if (_selectedPID == _productId)
                {
                    double _price = Convert.ToDouble(_productPrice);

                    Int64 _qty = Convert.ToInt64(txtQt.Text);

                    double Amount = _price * _qty;

                    
                    bool _alreadyExists = _productExists(_CustomerID, _productId);
                    if (_alreadyExists == true)
                    {
                        _UpdatedCart(_productId, _CustomerID, _qty);
                        //lblMessage.CssClass = "alert alert-danger";
                        //lblMessage.Text = "items Qty Updated..";
                        
                        ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "SweetAlert", "swal('Product Qty Updated..');", true);

                    }
                    else
                    {
                        _cartFunctions(Id, _productId, _qty, _CustomerID, Amount, _action);
                        //lblMessage.CssClass = "alert alert-success alert-dismissable fade in";
                        //lblMessage.Text = "items Added Successfully..";
                        Label lblfff = ((Label)Master.FindControl("Lbl_CartTotalAmt") );
                        DataSet ds = new DataSet();
                        ds=GetCartPrice();
                        lblfff.Text = ds.Tables[0].Rows[0][0].ToString();
                        ScriptManager.RegisterClientScriptBlock(this, this.GetType(), "SweetAlert", "swal('Product Added Successfully..');", true);

                    }
                }
            }
        }