.NET Core 2.0遷移技巧之web.config配置文件

你們都知道.NET Core如今再也不支持原來的web.config配置文件了，取而代之的是json或xml配置文件。官方推薦的項目配置方式是使用appsettings.json配置文件，這對現有一些重度使用web.cofig配置的項目遷移多是不可接受的。

可是好消息是，咱們是能夠直接在.NET Core 2.0項目種利用上現有的web.config的。

 

遷移方法

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　　　　1.首先在解決方案中引入System.Configuration.ConfigurationManager,只有引入它才能夠讓咱們已有的讀取web.config代碼起做用.

　　　　

　　　　2. 導入web.config文件到項目根目錄，並將名稱修改成app.config. 由於.NET Core的項目本質是控制檯應用，因此ConfigurationManager的API會去默認讀取app.config配置文件，而不是web.config配置文件。

 

 

　　　　3.去除config中和須要的配置無關的內容，主要是<system.web>,<system.webServer>和<system.codedom>等典型asp.net標籤。

　　　　移除前：

<?xml version="1.0" encoding="utf-8"?>
<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)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-WebApplication24-20170824065102.mdf;Initial Catalog=aspnet-WebApplication24-20170824065102;Integrated Security=True"
      providerName="System.Data.SqlClient" />
  </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" />
    <add key="MyKey" value="true"/>
  </appSettings>
  <system.web>
    <compilation debug="true" targetFramework="4.7" />
    <httpRuntime targetFramework="4.7" />
    <httpModules>
      <add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web" />
    </httpModules>
  </system.web>
  <runtime>
    <assemblyBinding xmlns="urn:schemas-microsoft-com:asm.v1">
      <dependentAssembly>
        <assemblyIdentity name="Newtonsoft.Json" culture="neutral" publicKeyToken="30ad4fe6b2a6aeed" />
        <bindingRedirect oldVersion="0.0.0.0-6.0.0.0" newVersion="6.0.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="System.Web.Optimization" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="1.0.0.0-1.1.0.0" newVersion="1.1.0.0" />
      </dependentAssembly>
      <dependentAssembly>
        <assemblyIdentity name="WebGrease" publicKeyToken="31bf3856ad364e35" />
        <bindingRedirect oldVersion="0.0.0.0-1.5.2.14234" newVersion="1.5.2.14234" />
      </dependentAssembly>
      <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.WebPages" 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="1.0.0.0-5.2.3.0" newVersion="5.2.3.0" />
      </dependentAssembly>
    </assemblyBinding>
  </runtime>
  <system.webServer>
    <validation validateIntegratedModeConfiguration="false" />
    <modules>
      <remove name="ApplicationInsightsWebTracking" />
      <add name="ApplicationInsightsWebTracking" type="Microsoft.ApplicationInsights.Web.ApplicationInsightsHttpModule, Microsoft.AI.Web" preCondition="managedHandler" />
    </modules>
  </system.webServer>
  <system.codedom>
    <compilers>
      <compiler language="c#;cs;csharp" extension=".cs" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.CSharpCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.5.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:default /nowarn:1659;1699;1701" />
      <compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" type="Microsoft.CodeDom.Providers.DotNetCompilerPlatform.VBCodeProvider, Microsoft.CodeDom.Providers.DotNetCompilerPlatform, Version=1.0.5.0, Culture=neutral, PublicKeyToken=31bf3856ad364e35" warningLevel="4" compilerOptions="/langversion:default /nowarn:41008 /define:_MYTYPE=\&quot;Web\&quot; /optionInfer+" />
    </compilers>
  </system.codedom>
</configuration>

　　修改後：

<?xml version="1.0" encoding="utf-8"?>
<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)\MSSQLLocalDB;AttachDbFilename=|DataDirectory|\aspnet-WebApplication24-20170824065102.mdf;Initial Catalog=aspnet-WebApplication24-20170824065102;Integrated Security=True"
      providerName="System.Data.SqlClient" />
  </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" />
    <add key="MyKey" value="true"/>
  </appSettings>
</configuration>

 

　　　　4.測試原ASP.NET代碼，查看讀取配置值

 

using System.Configuration;

namespace WebConfigTest.Configuration
{
    public class ConfigurationService
    {
        public static bool GetConfigValue(string key)
        {
            var result = false;
           var val= ConfigurationManager.AppSettings[key];
            if (val != null)
            {
                result = bool.Parse(val);
            }
            return result;
        }
    }
}

 

打個斷點，看下讀取配置值是否正確：

 

 

 大功告成，讀取的配置值徹底正確。

你們能夠使用這個方法快速遷移現有配置文件和代碼過去啦。