我是新手C＃dev和更新的Linq，但我正在试图弄清楚如何将Linq查询中的嵌套子对象转换为对象。我可以得到主/根对象。
到目前为止，这是我的代码和我正在使用的Json文件。注意，如果碰巧出现格式错误，我会手动从Json中删除一些文本。
class Program
{
static void Main(string[] args)
{
Program p = new Program();
p.processJson();
Console.ReadLine();
}
public void processJson()
{
JObject jobject = JObject.Parse(this.getSampleOrderJsonText());
// QUESTION IS IN THIS BLOCK OF CODE
var orders =
from p in jobject["resource"]["items"].Children()["resource"]
select new orderHeader
{
orderNo = (string)p["orderNo"],
status = (string)p["status"]
// How do I fill "lines" and its child object "lines.lineDetails"?
// lines =
};
foreach (orderHeader orderList in orders)
{
Console.WriteLine(orderList.orderNo + " " + orderList.status);
}
}
public class orderHeader
{
public string orderNo { get; set; }
public string status { get; set; }
public List<orderLine> lines { get; set; }
}
public class orderLine
{
public string sku { get; set; }
public int quantity { get; set; }
public List<orderLineDetail> lineDetails { get; set; }
}
public class orderLineDetail
{
public int productId { get; set; }
public string serialNumber { get; set; }
}
public string getSampleOrderJsonText()
{
return "{Entire Json Text}"; // This returns all the JsonText
}
}
这是我的（编辑过的）Json：
{
"status": 200,
"message": "Successful",
"resource": {
"offset": 0,
"total": 1,
"previous": null,
"next": null,
"items": [{
"resource": {
"orderNo": "#6255.1",
"lastUpdatedDate": "2016-01-21T17:39:36-08:00",
"status": "completed",
"vendorId": null,
"vendorExternalId": null,
"id": 153357642,
"items": {
"resource": {
"offset": 0,
"total": 3,
"previous": null,
"next": null,
"items": [{
"resource": {
"sku": "796430390315",
"quantity": 2,
"serialNumbers": {
"resourceLocation": null,
"resource": {
"offset": 0,
"total": 2,
"previous": null,
"next": null,
"items": [{
"resourceLocation": null,
"resource": {
"orderId": 153357642,
"productId": 3525462,
"serialNumber": "T8-0139062"
}
}, {
"resourceLocation": null,
"resource": {
"orderId": 153357642,
"productId": 3525462,
"serialNumber": "T8-0139063"
}
}]
}
},
"productId": 3525462,
"orderId": 153357642,
"ordered": 2,
"shipped": 1
}
}, {
"resource": {
"sku": "796430390322",
"quantity": 2,
"commercialInvoiceValue": 0,
"serialNumbers": {
"resourceLocation": null,
"resource": {
"offset": 0,
"total": 2,
"previous": null,
"next": null,
"items": [{
"resourceLocation": null,
"resource": {
"orderId": 153357642,
"productId": 3525472,
"serialNumber": "T8-0140454"
}
}, {
"resourceLocation": null,
"resource": {
"orderId": 153357642,
"productId": 3525472,
"serialNumber": "T8-0140478"
}
}]
}
},
"productId": 3525472,
"orderId": 153357642,
"ordered": 2,
"shipped": 1
}
}, {
"resourceLocation": null,
"resource": {
"sku": "796430390346",
"quantity": 1,
"commercialInvoiceValue": 0,
"serialNumbers": {
"resourceLocation": null,
"resource": {
"offset": 0,
"total": 1,
"previous": null,
"next": null,
"items": [{
"resourceLocation": null,
"resource": {
"orderId": 153357642,
"productId": 3525482,
"serialNumber": "T8-0141520"
}
}]
}
},
"productId": 3525482,
"orderId": 153357642,
"ordered": 1,
"shipped": 1
}
}]
}
}
"options": {
"resourceLocation": null,
"resource": {
"warehouseId": 13,
"warehouseRegion": "CHI",
"carrierCode": "FDX"
}
}
"shipTo": {
"resource": {
"email": "none@nowhere.com",
"name": "First Last",
"company": "Company, Inc",
"address1": "123 South Street",
"address2": "",
"address3": "",
"city": "Chicago",
"state": "IL",
"postalCode": "60652",
"country": "US",
"phone": "5555551234"
}
}
"pricing": {
"resourceLocation": null,
"resource": {
"shipping": 20.76,
"packaging": 0.88,
"insurance": 9,
"handling": 5.25,
"total": 35.89
}
}
}
}]
}
}
编辑：工作代码！这是最好的方法吗？如果子元素不存在怎么办？
public void processJson()
{
JObject jobject = JObject.Parse(this.getSampleOrderJsonText());
var orders =
from p in jobject["resource"]["items"].Children()["resource"]
select new orderHeader
{
orderNo = (string)p["orderNo"],
status = (string)p["status"],
lines = (
from nestedChildren in p["items"]["resource"]["items"].Children()["resource"]
select new orderLine
{
sku = (string)nestedChildren["sku"],
quantity = (int)nestedChildren["quantity"]
})
};
foreach (orderHeader orderList in orders)
{
Console.WriteLine(orderList.orderNo + " " + orderList.status);
if (orderList.lines != null)
{
foreach (orderLine line in orderList.lines.ToList())
{
Console.WriteLine("-->{0}: {1}", line.sku, line.quantity);
}
}
}
}
答案 0 :(得分：1)
如果有更好的方法来编写某个查询，问题肯定几乎与哲学相关。是不是有不同的方法呢？是的，还有很多！
linq的select / from语法当然深受SQL的启发，作为一种声明范式，与纯粹的命令式C类查询相比，它具有许多优点和缺点。
SQl风格的Linq：
扩展方法Linq：
类似的东西：
var MyQuery = MyDataStructure.Where( data => data.property == mySearchProperty )
.Distinct()
.Select( data => data.CustomerID );
C风格查询：
在非常大的数据和非常高的并行化的云中变得流行的另一种方法是NO-SQL语法;然而，这是一个独立的主题。
对于您必须承认的特定情况，我并不真正了解您的数据结构 - 尤其是
p["items"]["resource"]["items"].Children()["resource"]
让我困惑，似乎很不寻常。 但只要您获得所需的数据并且您的代码可读且易于维护，您就不会在这里出错。除非您有特定条件，如大量数据或时间问题，否则您的查询对我来说似乎完全没问题。