為什么在C＃中反序列化我的packages.config返回空值？

Question

我正在嘗試在C＃中反序列化我的packages.config文件，但是我得到的Collection始終為null。 如果我的xml文件包含單個屬性集合，是否需要一些特殊的東西？

[Serializable()]
[System.Xml.Serialization.XmlTypeAttribute()]
public class Package
{
    [System.Xml.Serialization.XmlAttribute("id")]
    public string Id {get;set;}
    [System.Xml.Serialization.XmlAttribute("version")]
    public string Version {get;set;}
}

[Serializable()]
[System.Xml.Serialization.XmlRoot("packages")]
public class PackageCollection
{
    [System.Xml.Serialization.XmlArrayItem("package", typeof(Package))]
    public Package[] Packages {get;set;}    
}


void Main()
{
    var path = "C:\D\packages.config";
    var serializer  = new System.Xml.Serialization.XmlSerializer(typeof(PackageCollection), new System.Xml.Serialization.XmlRootAttribute("packages"));
    StreamReader reader = new StreamReader(file);
    var packages2 = (PackageCollection)serializer.Deserialize(reader);
    reader.Close();
}

我的packages.config看起來像

<?xml version="1.0" encoding="utf-8"?> 
<packages> 
  <package id="Autofac" version="3.3.1" targetFramework="net45" /> 
  <package id="Microsoft.AspNet.WebApi.Client" version="4.0.20710.0" targetFramework="net45" /> 
  <package id="Microsoft.AspNet.WebApi.Core" version="4.0.20710.0" targetFramework="net45" /> 
  <package id="Microsoft.AspNet.WebApi.Tracing" version="4.0.30506" targetFramework="net45" /> 
  <package id="Microsoft.Net.Http" version="2.0.20710.0" targetFramework="net45" /> 
  <package id="Microsoft.Web.Infrastructure" version="1.0.0.0" targetFramework="net45" /> 
  <package id="Newtonsoft.Json" version="4.5.11" targetFramework="net45" /> 
</packages> 

Answer 1

在這種情況下，請使用XmlElement：

[Serializable()]
[System.Xml.Serialization.XmlRoot("packages")]
public class PackageCollection
{
    [System.Xml.Serialization.XmlElement("package", typeof(Package))]
    public Package[] Packages { get; set; }
}

Answer 2

根據包含的測試，此代碼似乎可以根據您的需要運行：

[Serializable()]
[System.Xml.Serialization.XmlTypeAttribute()]
public class Package
{
    [System.Xml.Serialization.XmlAttributeAttribute("id")]
    public string Id { get; set; }

    [System.Xml.Serialization.XmlAttributeAttribute("version")]
    public string Version { get; set; }

    [System.Xml.Serialization.XmlAttributeAttribute("targetFramework")]
    public string TargetFramework { get; set; }
}

[Serializable()]
[System.Xml.Serialization.XmlRoot("packages")]
public class PackageCollection
{
    [System.Xml.Serialization.XmlElementAttribute("package")]
    public Package[] Packages { get; set; }
}

class Program
{
    static void Main()
    {
        var path = @"C:\packages.config";
        var serializer = new System.Xml.Serialization.XmlSerializer(typeof(PackageCollection));
        StreamReader reader = new StreamReader(path);
        var packages2 = (PackageCollection)serializer.Deserialize(reader);
        foreach (Package pkg in packages2.Packages)
        {
            Console.WriteLine("ID: " + pkg.Id);
            Console.WriteLine("Version: " + pkg.Version);
            Console.WriteLine("Target Framework: " + pkg.TargetFramework);
            Console.WriteLine();              
        }     
        reader.Close();
        Console.ReadLine();
    }
}

正如@Isantipov所提到的， XML架構定義工具（Xsd.exe）-MDSN可以提供幫助。

另請參閱問題如何反序列化XML文檔以獲取一些其他信息，尤其是Marc Gravell的答案 。