如何下载服务器在Ajax调用中返回的文件？

我有一个下载功能，其想法是当用户单击一个按钮时，它将对一个函数进行ajax调用，该函数将创建一个包含用户正在查看的所有信息的csv文件，并将该文件作为下载返回。我有创建csv文件的服务器功能，但不确定如何下载它。这是我的服务器端代码：

public ActionResult Download(Guid customerOrderId)
{
    var order = this.UnitOfWork.GetRepository<CustomerOrder>().Get(customerOrderId);

    var csv = new StringBuilder();

    csv.Append("Customer,Bill To Name,Ship To Name,Patient,Order#,Order Date," +
        "Line,Item#,Item Description,Qty,UOM,Price,Ext Price,Carrier," +
        "Notes,Purchase Order");

    var customer = order.CustomerNumber;
    var billToName = order.BTDisplayName;
    var shipToName = order.ShipTo.CustomerName;
    var orderNum = order.OrderNumber;
    var orderDate = order.OrderDate;
    var carrier = order.ShippingDisplay;
    var notes = order.Notes;
    var subtotal = order.OrderSubTotalDisplay;
    var total = order.OrderGrandTotalDisplay;
    var shipping = order.ShippingAndHandling;
    var tax = order.TotalSalesTaxDisplay;
    var patient = "";
    var purchaseOrder = order.CustomerPO;
    foreach (var cartLine in order.OrderLines)
    {
        var line = cartLine.Line;
        var itemNum = cartLine.Product.ProductCode;
        var itemDesc = cartLine.Description;
        var qty = cartLine.QtyOrdered;
        var uom = cartLine.UnitOfMeasure;
        var price = cartLine.ActualPriceDisplay;
        var ext = cartLine.ExtendedActualPriceDisplay;

        //Customer,Bill To Name,Ship To Name,Patient,Order#,Order Date," + 
        //"Line,Item#,Item Description,Qty,UOM,Price,Ext Price,Carrier," +
        //"Notes,Purchase Order
        var newLine = string.Format("{0},{1},{2},{3},{4},{5},{6},{7},{8},{9},{10},{11},{12},{13},{14},{15}",
            customer, billToName, shipToName, patient, orderNum, orderDate, line, itemNum, itemDesc,
            qty, uom, price, ext, carrier, notes, purchaseOrder);

        csv.AppendLine(newLine);
    }

    csv.AppendLine();
    csv.AppendLine("Subtotal,Shipping & Handling,Tax,Total");
    csv.AppendLine(string.Format("{0},{1},{2},{3}", subtotal, shipping, tax, total));

    var filename = "MSD-Order-" + orderNum + ".csv";            

    var bytes = Encoding.UTF8.GetBytes(csv.ToString());
    return this.File(bytes, "text/csv");
}

这是ajax方法：

function download(customerOrderId) {
    $.ajax({
        url: insite.core.actionPrefix + '/Checkout/Download/?customerOrderId=' + customerOrderId,
        type: 'Post',
        contentType: "application/json; charset=utf-8",
        async: false,
        cache: false,
        success: function (data) {
            alert("downloaded");
        },
        error: function (ex) {
            console.log(ex);
        }
    });    
}

在成功执行ajax调用后，我检查了“数据”的值，它具有信息，但是我不确定如何下载它。收到数据后该怎么办？