C#操作项目配置文件

前言

对于项目配置文件的读取和修改，.net 提供了ConfigurationManager（位于System.Configuration命名空间） 和WebConfigurationManager（位于System.Web.Configuration命名空间）两个类，能够很方便的操作项目的配置文件。另外，对于 Web 应用程序配置，建议使用 WebConfigurationManager 类，而不要使用 ConfigurationManager 类。

演示

下面是一个asp.net mvc5项目的项目配置文件

Web.config

 <?xml version="1.0" encoding="utf-8"?>
 <!--
   有关如何配置 ASP.NET 应用程序的详细信息，请访问
   http://go.microsoft.com/fwlink/?LinkId=301880
   -->
 <configuration>
   <configSections>
     <!-- For more information on Entity Framework configuration, visit http://go.microsoft.com/fwlink/?LinkID=237468 -->
     <section name="entityFramework" type="System.Data.Entity.Internal.ConfigFile.EntityFrameworkSection, EntityFramework, Version=6.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089" requirePermission="false" />
   </configSections>
   <connectionStrings>
     <add name="DefaultConnection" connectionString="Data Source=(LocalDb)\v11.0;AttachDbFilename=|DataDirectory|\aspnet-WebApplication1-20160513023153.mdf;Initial Catalog=aspnet-WebApplication1-20160513023153;Integrated Security=True" providerName="System.Data.SqlClient" />
     <add name="MoocEntities" connectionString="metadata=res://*/Models.MOOC.csdl|res://*/Models.MOOC.ssdl|res://*/Models.MOOC.msl;provider=System.Data.SqlClient;provider connection string=&quot;data source=.;initial catalog=Mooc;user id=sa;password=aaaaaa;MultipleActiveResultSets=True;App=EntityFramework&quot;" providerName="System.Data.EntityClient" />
   </connectionStrings>
   <appSettings>
     <add key="webpages:Version" value="3.0.0.0" />
     <add key="webpages:Enabled" value="false" />
     <add key="ClientValidationEnabled" value="true" />
     <add key="UnobtrusiveJavaScriptEnabled" value="true" />
   </appSettings>
   <system.web>
     <authentication mode="None" />
     <compilation debug="true" targetFramework="4.5" />
     <httpRuntime targetFramework="4.5" />
   </system.web>
   <system.webServer>
     <modules>
       <remove name="FormsAuthenticationModule" />
     </modules>
   </system.webServer>
   <runtime>
     <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
       <dependentAssembly>
         <assemblyIdentity name="System.Web.Helpers" publicKeyToken="31bf3856ad364e35" />
         <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Web.Mvc" publicKeyToken="31bf3856ad364e35" />
         <bindingRedirect oldVersion="1.0.0.0-5.0.0.0" newVersion="5.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="System.Web.WebPages" publicKeyToken="31bf3856ad364e35" />
         <bindingRedirect oldVersion="1.0.0.0-3.0.0.0" newVersion="3.0.0.0" />
       </dependentAssembly>
       <dependentAssembly>
         <assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
         <bindingRedirect oldVersion="1.0.0.0-1.5.2.14234" newVersion="1.5.2.14234" />
       </dependentAssembly>
     </assemblyBinding>
   </runtime>
   <entityFramework>
     <defaultConnectionFactory type="System.Data.Entity.Infrastructure.LocalDbConnectionFactory, EntityFramework">
       <parameters>
         <parameter value="v11.0" />
       </parameters>
     </defaultConnectionFactory>
     <providers>
       <provider invariantName="System.Data.SqlClient" type="System.Data.Entity.SqlServer.SqlProviderServices, EntityFramework.SqlServer" />
     </providers>
   </entityFramework>
 </configuration>

获取与修改appSettings配置节点下的属性值

WebConfigurationManager提供了AppSettings属性，便于访问配置文件中appSettings节点下的元素的value值

下图为Web.config中要获取值的元素

编写如下代码，并在第27行打上断点调试

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
 using System.Web.Mvc;
 using System.Web.Configuration;
 using System.Text;
 using System.Collections.Specialized;
 using System.Collections;
 using System.Diagnostics;
 namespace WebApplication1.Controllers
 {
     public class HomeController : Controller
     {
         public ActionResult Index()
         {

             string version = WebConfigurationManager.AppSettings["webpages:Version"];
             string enabled = WebConfigurationManager.AppSettings["webpages:Enabled"];
             string clientValidationEnabled = WebConfigurationManager.AppSettings["ClientValidationEnabled"];
             string unobtrusiveJavaScriptEnabled = WebConfigurationManager.AppSettings["UnobtrusiveJavaScriptEnabled"];
             Debug.WriteLine("配置信息如下");
             Debug.WriteLine(version);
             Debug.WriteLine(enabled);
             Debug.WriteLine(clientValidationEnabled);
             Debug.WriteLine(unobtrusiveJavaScriptEnabled);
             return Content("");
         }

     }
 }

调试模式“输出”窗口

以WebConfigurationManager.AppSettings["ClientValidationEnabled"]="要修改的值" 可直接修改值

 using System;
 using System.Collections.Generic;
 using System.Linq;
 using System.Web;
 using System.Web.Mvc;
 using System.Web.Configuration;
 using System.Text;
 using System.Collections.Specialized;
 using System.Collections;
 using System.Diagnostics;
 namespace WebApplication1.Controllers
 {
     public class HomeController : Controller
     {
         public ActionResult Index()
         {

             string version = WebConfigurationManager.AppSettings["webpages:Version"];
             string enabled = WebConfigurationManager.AppSettings["webpages:Enabled"];
             WebConfigurationManager.AppSettings["ClientValidationEnabled"]="aaaaaaaaaaaaaaaaaaaaa";//动态修改value
             string clientValidationEnabled = WebConfigurationManager.AppSettings["ClientValidationEnabled"];
             string unobtrusiveJavaScriptEnabled = WebConfigurationManager.AppSettings["UnobtrusiveJavaScriptEnabled"];
             Debug.WriteLine("配置信息如下");
             Debug.WriteLine(version);
             Debug.WriteLine(enabled);
             Debug.WriteLine(clientValidationEnabled);
             Debug.WriteLine(unobtrusiveJavaScriptEnabled);
             return Content("");
         }

     }
 }

调试输出

连接字符串修改

 /*获取数据库连接字符串*/
 string moocConnection = WebConfigurationManager.ConnectionStrings["MoocEntities"].ConnectionString;
 Debug.WriteLine("连接字符串如下：");//打印
 Debug.WriteLine(moocConnection);//打印

未完待续-----