从app.config获取连接字符串，并在linq datacontext中使用它

Question

如何提取以下连接字符串并将其应用于我的LINQ上下文？我知道LINQ的部分，但对系统的配置部分很弱。

  <connectionStrings>
        <!-- Production

        <add name="Management_Report_Emailer.Properties.Settings.DWConnectionString"
            connectionString="Data Source=prodSQL01;Initial Catalog=DW;Integrated Security=True"
            providerName="System.Data.SqlClient" />-->


      <!-- QA-->

      <add name="Management_Report_Emailer.Properties.Settings.DWConnectionString"
            connectionString="Data Source=qaSQL01;Initial Catalog=DW;Integrated Security=True"
            providerName="System.Data.SqlClient" />
    </connectionStrings>

Answer 1

ConfigurationManager.ConnectionStrings("Management_Report_Emailer.Properties.Settings.DWConnectionString").ConnectionString

Answer 2

ConfigurationManager.ConnectionStrings["Management_Report_Emailer.Properties.Settings.DWConnectionString"].ConnectionString;