.NET：自定义配置节

背景

对于编译型应用程序来说，参数化程序行为是非常有必要的，.NET有其标准的配置方法，我们可以可以扩展。

示例

代码

 using System;
 using System.Collections;
 using System.Text;
 using System.Configuration;
 using System.Xml;

 namespace YEA.Infrastructure.Gateway.Config
 {
     public enum ExchangeType { direct, topic, fanout };
     public class Exchange : ConfigurationElement
     {
         [ConfigurationProperty("name", DefaultValue = "", IsRequired = true)]
         public string Name
         {
             get { return (string) this["name"]; }
             set { this["name"] = value; }
         }
         [ConfigurationProperty("connection", DefaultValue = "", IsRequired = true)]
         public string Connection
         {
             get { return (string)this["connection"]; }
             set { this["connection"] = value; }
         }
         [ConfigurationProperty("type", DefaultValue = "direct", IsRequired = true)]
         public ExchangeType Type
         {
             get { return (ExchangeType)this["type"]; }
             set { this["type"] = value; }
         }
         [ConfigurationProperty("autodelete", DefaultValue= true, IsRequired = false)]
         public bool AutoDelete
         {
             get { return (bool)this["autodelete"]; }
             set { this["autodelete"] = value; }
         }
         [ConfigurationProperty("durable", DefaultValue = false, IsRequired = false)]
         public bool Durable
         {
             get { return (bool)this["durable"]; }
             set { this["durable"] = value; }
         }
     }
     public class ExchangeCollection : ConfigurationElementCollection
     {
         public override ConfigurationElementCollectionType CollectionType
         {
             get
             {
                 return ConfigurationElementCollectionType.AddRemoveClearMap;
             }
         }
         protected override ConfigurationElement CreateNewElement()
         {
             return new Exchange();
         }
         protected override object GetElementKey(ConfigurationElement element)
         {
             return ((Exchange)element).Name;
         }
         public new string AddElementName
         {
             get { return base.AddElementName; }
             set { base.AddElementName = value; }
         }
         public new string ClearElementName
         {
             get { return base.ClearElementName; }
             set { base.ClearElementName = value; }

         }

         public new string RemoveElementName
         {
             get { return base.RemoveElementName; }
         }

         public new int Count
         {
             get { return base.Count; }
         }

         public Exchange this[int index]
         {
             get
             {
                 return (Exchange)BaseGet(index);
             }
             set
             {
                 if (BaseGet(index) != null)
                 {
                     BaseRemoveAt(index);
                 }
                 BaseAdd(index, value);
             }
         }

         new public Exchange this[string Name]
         {
             get { return (Exchange)BaseGet(Name); }
         }

         public int IndexOf(Exchange exchange)
         {
             return BaseIndexOf(exchange);
         }

         public void Add(Exchange exchange)
         {
             BaseAdd(exchange);
             // Add custom code here.
         }

         protected override void BaseAdd(ConfigurationElement element)
         {
             BaseAdd(element, false);
             // Add custom code here.
         }

         public void Remove(Exchange exchange)
         {
             if (BaseIndexOf(exchange) >= )
                 BaseRemove(exchange.Name);
         }

         public void RemoveAt(int index)
         {
             BaseRemoveAt(index);
         }

         public void Remove(string name)
         {
             BaseRemove(name);
         }

         public void Clear()
         {
             BaseClear();
             // Add custom code here.
         }
     }
     public class AMQPObjectsDeclarationSection : ConfigurationSection
     {
         [ConfigurationProperty("ExchangeList", IsDefaultCollection = false)]
         public ExchangeCollection ExchangeList
         {
             get
             {
                 ExchangeCollection exchanges = (ExchangeCollection)this["ExchangeList"];
                 return exchanges;
             }
         }
         [ConfigurationProperty("QueueList", IsDefaultCollection = false)]
         public QueueCollection QueueList
         {
             get
             {
                 QueueCollection queue = (QueueCollection)this["QueueList"];
                 return queue;
             }
         }
         [ConfigurationProperty("BindingList", IsDefaultCollection = false)]
         public BindingCollection BindingList
         {
             get
             {
                 BindingCollection binding = (BindingCollection)this["BindingList"];
                 return binding;
             }
         }

         protected override void DeserializeSection(System.Xml.XmlReader reader)
         {
             base.DeserializeSection(reader);
             // You can add custom processing code here.
         }

         protected override string SerializeSection(
             ConfigurationElement parentElement,
             string name, ConfigurationSaveMode saveMode)
         {
             string s =
                 base.SerializeSection(parentElement,
                 name, saveMode);
             // You can add custom processing code here.
             return s;
         }

     }
 }

最终XML配置

App.config

 <?xml version="1.0" encoding="utf-8" ?>
 <configuration>
   <configSections>
     <sectionGroup name="AMQPConnection">
       <section name="ConnectionSettings"
                      type="YEA.Infrastructure.Gateway.Config.ConnectionSection, YEA.Infrastructure.Gateway"></section>
     </sectionGroup>
     <sectionGroup name="AMQPAdmin">
       <section name="AMQPObjectsDeclaration"
                type="YEA.Infrastructure.Gateway.Config.AMQPObjectsDeclarationSection, YEA.Infrastructure.Gateway"
                allowLocation="true"
                allowDefinition="Everywhere"></section>
     </sectionGroup>

   </configSections>
   <AMQPConnection >
     <ConnectionSettings configSource="Config\amqp.connection.config"/>
   </AMQPConnection>
   <AMQPAdmin>
     <AMQPObjectsDeclaration configSource="Config\amqp.objects.config"/>
   </AMQPAdmin>
   <appSettings >
     <add key="SleepTime" value="0"></add>
     <!--Mode = ["Receiver","Transmitter"]-->
     <add key="Mode" value="Receiver"></add>
     <add key="DummyFile" value="C:\logs\YEA\Monitor\LogService.txt"></add>
     <add key="notificationToEmail" value="ruben.rotteveel@chamberlain.com"/>
     <add key="notificationFromEmail" value="webmaster@chamberlain.com"/>
   </appSettings>
 </configuration>

amqp.connection.config

 <?xml version="1.0" encoding="utf-8" ?>
 <ConnectionSettings>
   <ConnectionList>
     <add name="Connection" server="localhost" username="guest" password="guest"></add>
   </ConnectionList>
   <PublisherList>
     <add name="orderPublisher" connection="Connection" exchange="orders" ></add>
     <add name="notificationPublisher" connection="Connection" exchange="notificationExchange"></add>
     <add name="logPublisher" connection="Connection" exchange="logExchange"></add>
   </PublisherList>
   <AsyncReceiverList>
     <add name="orderReceiver" connection="Connection" queue="uk_orders, marketingemails, Accounting, CustomerService" maxthreads="40"></add>
     <add name="notificationReceiver" connection="Connection" queue="notificationQueue" maxthreads ="1"></add>
     <add name="logReceiver" connection="Connection" queue="logQueue" maxthreads ="1"></add>
   </AsyncReceiverList>
 </ConnectionSettings>

amqp.objects.config

 <?xml version="1.0" encoding="utf-8" ?>
 <AMQPObjectsDeclaration>
   <ExchangeList>
     <add name="orders" connection="Connection" type="topic" autodelete="false" durable="true"></add>
     <add name="shipments" connection="Connection" type ="topic" autodelete="false" durable="true"></add>
     <add name="logExchange" connection="Connection" type="topic" autodelete="false" durable="true"></add>
     <add name="notificationExchange" connection="Connection" type="topic" autodelete="false" durable="true"></add>
   </ExchangeList>
   <QueueList>
     <add name="uk_orders" connection="Connection" autodelete="false" durable="true"></add>
     <add name="us_orders" connection="Connection" autodelete="false" durable="true"></add>
     <add name="marketingemails" connection="Connection" autodelete ="false" durable="true"></add>
     <add name="Accounting" connection="Connection" autodelete="false" durable="true" ></add>
     <add name="CustomerService" connection="Connection" autodelete="false" durable="true" ></add>
     <add name="logQueue" connection="Connection" autodelete="false" durable="true"></add>
     <add name="notificationQueue" connection="Connection" autodelete="false" durable="true"></add>
   </QueueList>
   <BindingList>
     <add queue="uk_orders" connection="Connection" exchange="orders" subscriptionkey="order.uk.#"></add>
     <add queue="us_orders" connection="Connection" exchange="orders" subscriptionkey="order.us.#"></add>
     <add queue="marketingemails" connection="Connection" exchange="shipments" subscriptionkey="#" ></add>
     <add queue="marketingemails" connection="Connection" exchange="orders" subscriptionkey="#" ></add>
     <add queue="Accounting" connection="Connection" exchange="shipments" subscriptionkey="#" ></add>
     <add queue="Accounting" connection="Connection" exchange="orders" subscriptionkey="#" ></add>
     <add queue="CustomerService" connection="Connection" exchange="shipments" subscriptionkey="#" ></add>
     <add queue="CustomerService" connection="Connection" exchange="orders" subscriptionkey="#" ></add>
     <add queue="logQueue" connection="Connection" exchange="logExchange" subscriptionkey="#"></add>
     <add queue="notificationQueue" connection="Connection" exchange="notificationExchange" subscriptionkey="#"></add>
   </BindingList>
 </AMQPObjectsDeclaration>

读取配置

             var config = ConfigurationManager.OpenExeConfiguration(ConfigurationUserLevel.None);
             var objects = config.GetSection("AMQPAdmin/AMQPObjectsDeclaration") as AMQPObjectsDeclarationSection;

备注

简单的使用配置并不是最好的方式，比如：在控制台程序中，最好提供两种方式：通过命令行参数和配置结合，然后采用适当的优先级处理。另外，采用JSON配置可能会更简单一点。