OData V4客户端添加子实体 [英] OData V4 client adding child entity
问题描述
我有一个父级(订单)和一个子级(OrderDetail)，其中数据库中已经存在Order，数据库中也存在OrderDetail. 我真正想做的就是添加另一个与Order绑定的OrderDetail记录.
I have a parent (Order) and child (OrderDetail) where Order already exists in the database and OrderDetail also exists in the database.
All I really want to do is add another OrderDetail record bound to the Order.
我走了好几条路，我什至不确定什么是正确的路.
让我们假设它们之间的导航已经起作用.
我可以罚款$ expand = OrderDetails，也可以罚款Orders(1)/OrderDetails，并从OrderDetails进行相反的操作.
I have been down several paths and I'm not even sure what is the correct path.
Let's make some assumptions that navigations between these are already working.
I can $expand=OrderDetails fine and I can also Orders(1)/OrderDetails fine and do the reverse from OrderDetails.
基于此 更新数据服务 ，我需要做的就是调用AddRelatedObject，然后将对象添加到OrderDetails集合中.
Based on this Updating the Data Service, all I need to do is call AddRelatedObject and then Add the object to the OrderDetails collection.
// Add the new item with a link to the related Order
context.AddRelatedObject(order, "OrderDetails", newOrderDetail);
// Add the new order detail to the collection
order.Order_Details.Add(newOrderDetail);
newOrderDetail.Order = order;
看起来很简单.
但是，当我执行context.SaveChanges(SaveChangesOptions.ReplaceOnUpdate)时，它将引发错误.
Seems simple enough.
Yet when I execute context.SaveChanges(SaveChangesOptions.ReplaceOnUpdate) it will throw an error.
{"error":{"code":"","message":"No HTTP resource was found that matches the request URI 'http://localhost/Test/odata/Orders(1)/OrderDetails'.","innererror":{"message":"No routing convention was found to select an action for the OData path with template '~/entityset/key/navigation'.","type":"","stacktrace":""}}}
但是，如果我导航到列出的URL，它将显示数据.
提琴手的时间.
在Fiddler中，我可以看到这是URL的POST，而不是GET.
应该是POST而不是列出的URL.
POST应该已经到/odata/OrderDetails
But if I navigate to the URL listed, it shows data.
Time for Fiddler.
In Fiddler, I can see this is a POST to the URL and not a GET.
Which it should be a POST but not to the URL listed.
The POST should have been to /odata/OrderDetails
第二回合
// Add the new item with a link to the related Order
context.AttachTo("OrderDetails", newOrderDetail);
// Add a link between Order and the new OrderDetail
context.AddLink(order, "OrderDetails", newOrderDetail);
// Add the new order detail to the collection
order.Order_Details.Add(newOrderDetail);
newOrderDetail.Order = order;
仍然是POST并带有错误，但URL略有不同，并且发布的json仅具有"/odata/OrderDetail(0)"，现在还具有"$ ref".
Still a POST with an error but the URL is slightly different and the json posted only has "/odata/OrderDetail(0)" it also now has "$ref".
{"error":{"code":"","message":"No HTTP resource was found that matches the request URI 'http://localhost/Test/odata/Orders(1)/OrderDetails/$ref'.","innererror":{"message":"No routing convention was found to select an action for the OData path with template '~/entityset/key/navigation/$ref'.","type":"","stacktrace":""}}}
通过快速的网络搜索，我找到了这篇文章
我确实在Orders控制器中创建了一个"CreateRef"，并确保它足够被调用，但本文假设OrderDetail存在于数据库中.
它没有发布json OrderDetail对象.
Well a quick web search led me to this article Entity Relations in OData v4 Using ASP.NET Web API 2.2
This article says I need to add a "CreateRef" in the Orders controller.
I did create a "CreateRef" in the Orders controller and sure enough it gets called BUT the article assumes the OrderDetail exists in the database.
It is not posting the json OrderDetail object.
第三回合
// Add the new item with a link to the related Order
context.AttachTo("OrderDetails", newOrderDetail);
// Attach a link between Order and the new OrderDetail
context.AttachLink(order, "OrderDetails", newOrderDetail);
// Add the new order detail to the collection
order.Order_Details.Add(newOrderDetail);
newOrderDetail.Order = order;
这看起来好多了.
没有错误，但没有完全起作用.
它向/odata/OrderDetails(0)发送了一个PUT，并且确实向json发送了OrderDetail对象，但这应该是 POST而不是PUT .
Well this seems much better.
No error but it did not fully work.
It sent a PUT to the /odata/OrderDetails(0) and it did send the json OrderDetail object BUT this should have been a POST not a PUT.
我觉得我已经很近了，但我似乎还不知道如何使它正常工作.
I feel I am so close yet I can't seem to figure out how to get it to work properly.
有什么想法吗?
推荐答案
经过反复试验，我发现了一些可行的方法.
After trial and error I found something that worked.
// create a new order detail
OrderDetail newOrderDetail = new OrderDetail();
// set the orderID on the new order detail
newOrderDetail.OrderID = order.ID;
// add the order back as a link on the order detail
newOrderDetail.Order = order;
// add the order detail to the order detail collection on the order
order.OrderDetails.Add(newOrderDetail);
// add the order detail to the context
context.AddToOrderDetail(newOrderDetail);
// now update context for the order
context.UpdateObject(order);
// now save
context.SaveChanges();
这篇关于OData V4客户端添加子实体的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！
