ConfigurationSection类使用心得

ConfigurationSection类主要是方便我们用于扩展自定义webcongfig中的节点信息。我们可以方便的通过以下方式获取【自定义节点对象】

【你自定义的对象】 config = (【你自定义的对象】)ConfigurationManager.GetSection("【你自定义的节点名称，如果是sectiongroup的话，请使用XPATH方式】");

使用自定义节点，可能会涉及到这几个对象的使用：ConfigurationSection【配置域】、ConfigurationElement【节点】、ConfigurationElementCollection【节点列表】

用法一： 配置如下webconfig自定义信息，注意order和lineItem节点都是允许重复出现的 

 1<?xml version="1.0" encoding="utf-8" ?>
 2<configuration>
 3  <configSections>
 4    <section name="orders" type="ConsoleTest.OrdersSection, ConsoleTest"/>
 5  </configSections>
 6  <orders companyID="2001">
 7    <order number="100001" amount="222.22">
 8      <lineItems warehouseNumber="02">
 9        <lineItem number="00-000-001" description="wii"/>
10      </lineItems>
11    </order>
12    <order number="300001" amount="33.33">
13      <lineItems warehouseNumber="99">
14        <lineItem number="00-000-001" description="xbox 360"/>
15        <lineItem number="00-000-003" description="playstation 3"/>
16      </lineItems>
17    </order>
18  </orders>
19</configuration>

下面我们要定义相应的实体对象，该实体对象中会有一个子对象【用来表示节点列表信息】（ConfigurationElementCollection）

 public class OrdersSection : ConfigurationSection
    {
        [ConfigurationProperty("companyID", IsRequired = true)]
        public string CompanyID
        {
            get
            {
                return (string)base["companyID"];
            }
            set
            {
                base["companyID"] = value;
            }
        }

        [ConfigurationProperty("", IsDefaultCollection = true)]
        public OrderElementCollection Orders
        {
            get
            {
                return (OrderElementCollection)base[""];
            }
        }
    }

 接下来我们在看看节点列表对象的定义，其中会包含一个子对象【ConfigurationElementCollection】

public class OrderElementCollection : ConfigurationElementCollection
    {
        protected override ConfigurationElement CreateNewElement()
        {
            return new OrderElement();
        }
        protected override object GetElementKey(ConfigurationElement element)
        {
            return ((OrderElement)element).Number;
        }

        public override ConfigurationElementCollectionType CollectionType
        {
            get
            {
                return ConfigurationElementCollectionType.BasicMap;
            }
        }
        protected override string ElementName
        {
            get
            {
                return "order";
            }
        }

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

 那么我们再看看节点对象的定义

public class OrderElement : ConfigurationElement
    {
        [ConfigurationProperty("number", IsRequired = true)]
        public string Number
        {
            get
            {
                return (string)base["number"];
            }
            set
            {
                base["number"] = value;
            }
        }

        [ConfigurationProperty("amount", IsRequired = true)]
        public double Amount
        {
            get
            {
                return (double)base["amount"];
            }
            set
            {
                base["amount"] = value;
            }
        }

        [ConfigurationProperty("lineItems", IsDefaultCollection = true)]
        public LineItemElementCollection LineItems
        {
            get
            {
                return (LineItemElementCollection)base["lineItems"];
            }
        }
    }

另外，还有一个子节点列表对象需要定义，【LineItemElementCollection】(ConfigurationElementCollection)

 public class LineItemElementCollection : ConfigurationElementCollection
    {
        [ConfigurationProperty("warehouseNumber", IsRequired = true)]
        public string WarehouseNumber
        {
            get
            {
                return (string)base["warehouseNumber"];
            }
            set
            {
                base["warehouseNumber"] = value;
            }
        }

        protected override ConfigurationElement CreateNewElement()
        {
            return new LineItemElement();
        }
        protected override object GetElementKey(ConfigurationElement element)
        {
            return ( (LineItemElement)element ).Number;
        }

        public override ConfigurationElementCollectionType CollectionType
        {
            get
            {
                return ConfigurationElementCollectionType.BasicMap;
            }
        }
        protected override string ElementName
        {
            get
            {
                return "lineItem";
            }
        }

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

当然我们还得再定义一个节点对象【LineItemElement

 public class LineItemElement : ConfigurationElement
    {
        [ConfigurationProperty("number", IsKey=true, IsRequired = true)]
        public string Number
        {
            get
            {
                return (string)base["number"];
            }
            set
            {
                base["number"] = value;
            }
        }

        [ConfigurationProperty("description", IsRequired = true)]
        public string Description
        {
            get
            {
                return (string)base["description"];
            }
            set
            {
                base["description"] = value;
            }
        }
    }

这样我们就完成了webconfig节点的自定义和对象的实体化， 我们在使用的使用值需要简单的代码就能获取到相应对象的实体信息；如：

OrdersSection config = (OrdersSection)ConfigurationManager.GetSection("orders");

另一中用法：sectionGroup 配置 。如要配置出如下webconfig信息

 <configSections>
    <sectionGroup name="mygroup">
      <section name="mysection"
                       type="ConfigSection"
                        allowDefinition="Everywhere"
                         allowLocation="true"/>
    </sectionGroup>
  </configSections>

  <mygroup>
    <mysection  user="用户" password="密码">
      <element element1="属性1" element2="属性2"></element>
    </mysection>
  </mygroup>

 那么我们看下实体是如何定义的 。

using System;
using System.Data;
using System.Configuration;
using System.Web;
using System.Web.Security;
using System.Web.UI;
using System.Web.UI.WebControls;
using System.Web.UI.WebControls.WebParts;
using System.Web.UI.HtmlControls;

/// <summary>
/// ConfigSection 的摘要说明
/// </summary>
public class ConfigSection:ConfigurationSection
{
    public ConfigSection()
    {
        //
        // TODO: 在此处添加构造函数逻辑
        //
    }
[ConfigurationProperty("user",DefaultValue="yanghong",IsRequired=true)]
    public string User
    {
        get { return (string)this["user"]; }
        set { this["user"] = value; }
    }

    [ConfigurationProperty("password",DefaultValue="password",IsRequired=true)]
    public string PassWord
    {
        get {  return (string)this["password"]; }
        set { this["password"] = value; }
    }

    [ConfigurationProperty("element")]
    public elementinfo Element
    {
        get { return  (elementinfo)this["element"]; }
        set {this["element"] = value; }
    }
}

上面的实体对象包含一个节点对象信息，我们看下这个对象是如何定义的 。

public class elementinfo : ConfigurationElement
{
    public elementinfo()    { }


    [ConfigurationProperty("element1", DefaultValue = "element1", IsRequired = true)]
    public string Element1
    {
        get { return (string)this["element1"]; }
    }

    [ConfigurationProperty("element2",DefaultValue="element2",IsRequired=true)]
    public string Element2
    {
        get { return (string)this["element2"]; }
    }


}

代码的调用就相当简单了 ：

ConfigSection config = (ConfigSection)ConfigurationManager.GetSection("mygroup/mysection");
    Response.Write("用户名:"+config.User.ToString() + "密码:" + config.PassWord.ToString() + "元素属性:" + config.Element.Element1.ToString() + config.Element.Element2.ToString());