連接字符串中無法識別的元素

Question

找不到我的連接字符串出了什么問題：

我得到這個例外：

System.Configuration.ConfigurationErrorsException：配置系統無法初始化---> System.Configuration.ConfigurationErrorsException：無法識別的元素。 （D：\\ C＃\\ learncsharp \\ Data access \\ AsyncSQL \\ AsyncSQL \\ bin \\ Debug \\ AsyncSQL.exe.Config第2行）

這是我的代碼：

string connectionString = null;
string MovieDBContext = null;

try
{
    MovieDBContext = ConfigurationManager.ConnectionStrings["MovieDBContext"].ConnectionString;
    connectionString = ConfigurationManager.ConnectionStrings["ProgrammingInCSharpConnection"].ConnectionString;
}
catch (Exception e)
{
    Console.WriteLine( e.ToString() );
}

App.config：

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
    <connectionStrings>
        <add name="MovieDBContext"
             connectionString="Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\Movies.mdf;Integrated Security=True"
             providerName="System.Data.SqlClient" />
        <add name="ProgrammingInCSharpConnection" 
             connectionString="Data Source=(localdb)\v11.0;Initial Catalog=ProgrammingInCSharp;"
             providerName="System.Data.SqlClient" />
    </connectionStrings>
    <startup> 
        <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.5.2" />
    </startup>
</configuration>

怎么了？ 以及如何獲取哪個元素錯誤的詳細信息？

Answer 1

確保已在<configSections>元素中定義了該部分。按如下所示更改配置，

<?xml version="1.0" encoding="utf-8" ?>
<configuration>
   <configSections />
    <connectionStrings>
         <add name="MovieDBContext"
            connectionString="Data Source=(LocalDB)\v11.0;AttachDbFilename=|DataDirectory|\Movies.mdf;Integrated Security=True"
            providerName="System.Data.SqlClient"
        />
         <add name="ProgrammingInCSharpConnection" 
              providerName="System.Data.SqlClient" 
              connectionString="Data Source=(localdb)\v11.0;Initial Catalog=ProgrammingInCSharp;"
        />
    </connectionStrings>
</configuration>