ASP.NET MVC控制器动作-代码混乱运行

Question

I have really no ideea how to ask this. I have a set of async actions in my controller, one of which should populate a list through a foreach statement. The strange thing is, imagine I have 10 lines of code, it runs line 1 then jumps to line 4 then line 10 then line 1 again, at one point, the list has all the items it should but then it jumps again to the first line where I declared that list and then it exists with the empty list. Can anyone explain why this happens and how to fix it?

Here is the action in question

[HttpGet]
public async Task<ActionResult> GetBuyingListItems(string buyingListId, string vendorId, string orderId)
{
    var buyingListService = new BuyingListService(_buyingListRepository);
    ItemService itemService = new ItemService(_itemRepository);
    var vendorService = new VendorService(_vendorRepository);
    om.BuyingList = await buyingListService.GetOne(buyingListId);
    om.BuyingListItems = await buyingListService.GetBuyingListItems(buyingListId);
    om.Vendor = await vendorService.GetOne(vendorId);
    om.ItemsList = new List<OrderItemsDTO>();
    foreach (var buyingListItem in om.BuyingListItems)
    {
        var item = await itemService.GetOne(buyingListItem.ItemId);
        var orderItem = new OrderItemsDTO();
        orderItem.OrderId = orderId;
        orderItem.ItemID = item.Id;
        orderItem.Qty = buyingListItem.Qty;
        orderItem.TotalPrice = item.UnitPrice * buyingListItem.Qty;
        orderItem.Currency = om.Vendor.Currency;
        orderItem.VendorId = om.Vendor.Id;
        om.ItemsList.Add(orderItem);
    }

    return RedirectToAction("ItemListWithBuyingList", new { vendorId = vendorId, orderId = orderId, ItemsList = om.ItemsList });
}

om -> this is the model, i declered it for the entire controller.

Ps I have no ideea how to formulate this question in order to search for the answer so sorry if it's already been answered.

pps this isn't the only method that runs like this but i never had this problem until now. I always assumed it's because it runs asynchroniously.

ppps this might help, if i'm debuging from the browser, on the network part, my ajax calls are being made multiple times (for instance: first time - 3 times, then 6, then 12, etc... ). I am returning false on my ajax calls and there's no href="#" in my code.

Thank you.

Answer 1

What you are seeing is quite common when deubgging code that is being accessed by multiple threads. It looks chaotic but it's simply down to debugging jumping across different threads.

As a start you can use "lock" to avoid this during debugging so you can concentrate on the business logic not the threading issue.