发生ConfigurationErrorsException

Question

我想为C＃应用程序创建自定义配置。 app.config喜欢：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="location" type ="FolderConfigSection.LocationConfig, FolderConfigSection"/>
  </configSections>
  <location>
    <folders>
      <add folder ="C:\Test1"/>
      <add folder ="C:\Test2" />
      <add folder ="C:\Test3" />
    </folders>
  </location>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
  </startup>
</configuration>

所以我创建了两个类。

namespace FolderConfigSection
{
    public class LocationConfig : ConfigurationSection
    {
        [ConfigurationProperty("folders")]
        public string Folder
        {
            get { return base["folder"] as string; }
            set { base["folder"] = value; }
        }
    }
}

并且

namespace FolderConfigSection
{
    public class FolderCollection : ConfigurationElementCollection
    {
        protected override ConfigurationElement CreateNewElement()
        {
            return new FolderElement();
        }

        protected override object GetElementKey(ConfigurationElement element)
        {
            return ((FolderElement)element).Environment;
        }
    }

    public class FolderElement : ConfigurationElement
    {
        [ConfigurationProperty("folder", IsRequired = true)]
        public string Environment
        {
            get { return (string)this["folder"]; }
            set { this["folder"] = value; }
        }
    }
}

但是我的Program.cs中有一个例外

public class Program
{
    public static void Main(string[] args)
    {
        LocationConfig _locationConfig = (LocationConfig)ConfigurationManager.GetSection("location");
        string firstFolder = _locationConfig.Folder;

    }
}

例外是The section name 'location' is reserved for <location> sections. 我还要列出所有文件夹。

Answer 1

我正在重述@Tim在评论中回答的内容。

1. 请勿使用location作为部分名称。它已经为<location>元素配置保留。只需使用其他名称，例如locationConfig。
2. 将Folder课程中的LocationConfig媒体资源类型从String更改为FolderCollection。为清楚起见，您应该将属性名称Folder更改为复数形式Folders。
3. 要列出LocationConfig中的所有文件夹，您只需要迭代Folders集合属性。您可能还希望在FolderCollection类上实现索引器，以便对Folders属性进行索引访问。

全部放在代码中：

的App.config

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
  <configSections>
    <section name="locationConfig" type ="FolderConfigSection.LocationConfig, FolderConfigSection"/>
  </configSections>
  <locationConfig>
    <folders>
      <add folder ="C:\Test1"/>
      <add folder ="C:\Test2" />
      <add folder ="C:\Test3" />
    </folders>
  </locationConfig>
  <startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5" />
  </startup>
</configuration>

LocationConfig

namespace FolderConfigSection
{
  using System.Configuration;

  public class LocationConfig : ConfigurationSection
  {
    // Change the property type to FolderCollection, and
    // change the property name to `Folders` for clarity
    [ConfigurationProperty("folders")]
    public FolderCollection Folders
    {

      get { return base["folders"] as FolderCollection; }

      // the setter property isn't really needed here
      // set { base["folders"] = value; }
    }
  }

  public class FolderCollection : ConfigurationElementCollection
  {
    protected override ConfigurationElement CreateNewElement()
    {
      return new FolderElement();
    }

    protected override object GetElementKey(ConfigurationElement element)
    {
      return ((FolderElement)element).Environment;
    }

    // indexer
    public FolderElement this[int index]
    {
      get { return BaseGet(index) as FolderElement; }      
    }
  }

  public class FolderElement : ConfigurationElement
  {
    [ConfigurationProperty("folder", IsRequired = true)]
    public string Environment
    {
      get { return (string)this["folder"]; }
      set { this["folder"] = value; }
    }
  }
}

Program.cs的

public class Program
{
  static void Main(string[] args)
  {
    var locationConfig = (LocationConfig)ConfigurationManager.GetSection("locationConfig");

    foreach (FolderElement folder in locationConfig.Folders)
    {
      // List all folders
      Console.WriteLine(folder.Environment);        
    }    

    // The first folder using indexer property
    Console.WriteLine(locationConfig.Folders[0].Environment);
  }
}