App.config不起作用？

Question

我有我的App.Config像这样:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>

 <connectionStrings>
    <add 
      name="MyProject.Properties.Settings.Default.dataConnection"
      connectionString="Data Source=.\SQLEXPRESS;AttachDbFilename=address;
              Integrated Security=True;Connect Timeout=30;User Instance=True"
      providerName="System.Data.SqlClient" />
  </connectionStrings>
</configuration>

当我想使用下面的代码来获取连接字符串时,"错误1"Weather.Properties.Settings'不包含'dataConnection'的定义,也没有扩展方法'dataConnection'接受类型'Weather.Properties的第一个参数.可以找到"设置"(您是否缺少使用指令或程序集引用？)"错误上升,

string connectionString = 
   global::MyProject.Properties.Settings.Default.dataConnection;

Answer 1

要从配置文件中检索连接字符串,可以使用ConnectionStrings属性:

string connectionString = ConfigurationManager
    .ConnectionStrings["MyProject.Properties.Settings.Default.dataConnection"]
    .ConnectionString;