Linq到XML嵌套查詢

Question

我有一個問題讓LINQ查詢工作。我有這樣的XML：

<devices> 
    <device id ="2142" name="data-switch-01"> 
    <interface id ="2148" description ="Po1"/> 
    </device> 
    <device id ="2302" name="data-switch-02"> 
    <interface id ="2354" description ="Po1"/> 
    <interface id ="2348" description ="Gi0/44" /> 
    </device> 
</devices> 

而這種代碼：

var devices = from device in myXML.Descendants("device") 
       select new 
       { 
        ID = device.Attribute("id").Value, 
        Name = device.Attribute("name").Value, 
       }; 

foreach (var device in devices) 
{ 
    Device d = new Device(Convert.ToInt32(device.ID), device.Name); 

    var vIfs = from vIf in myXML.Descendants("device") 
        where Convert.ToInt32(vIf.Attribute("id").Value) == d.Id 
        select new 
        { 
         ID = vIf.Element("interface").Attribute("id").Value, 
         Description = vIf.Element("interface").Attribute("description").Value, 
        }; 
    foreach (var vIf in vIfs) 
    { 
     DeviceInterface di = new DeviceInterface(Convert.ToInt32(vIf.ID), vIf.Description); 
     d.Interfaces.Add(di); 
    } 

    lsDevices.Add(d); 
} 

我的設備對象包含了我需要從XML填充DeviceInterfaces的名單。目前我的代碼只填充第一個接口，後面的接口都被忽略，我不明白爲什麼。

我也很感激任何意見，這是否是正確的方式來做到這一點。嵌套foreach循環似乎有點亂給我

乾杯

Answer 1

IEnumerable<Device> devices = 
    from device in myXML.Descendants("device") 
    select new Device(device.Attribute("id").Value, device.Attribute("name").Value) 
    { 
    Interfaces = (from interface in device.Elements("Interface") 
        select new DeviceInterface(
         interface.Attribute("id").Value, 
         interface.Attribute("description").Value) 
       ).ToList() //or Array as you prefer 
    } 

這裏最基本的一點是，你做的一種「再選擇」設備上（這是一個​​），求所有Interface元素它包含。

它爲每個設備下的每個「接口」創建一個新的DeviceInterface。

Answer 2

快速和骯髒的

var query = from device in document.Descendants("device") 
      select new 
      { 
       ID = device.Attribute("id").Value, 
       Name = device.Attribute("name").Value, 
       Interfaces = from deviceInterface in device.Descendants("interface") 
          select new 
          { 
           ID = deviceInterface.Attribute("id").Value, 
           Description = deviceInterface.Attribute("description") 
          } 
      };