是否有可能改变一个的app.config在运行时连接字符串值？据the MSDN文档应该尽可能ConnectionString属性获取或设置连接字符串。

我的code是这样的：

  ConnectionStringSettings mainConnection = ConfigurationManager.ConnectionStrings [mainConnection];
mainConnection.ConnectionString =数据源=服务器;初始目录=+ NewDatabaseName +;集成安全性=真;
 

这是我收到的错误是这样的：未处理的异常：System.Configuration.ConfigurationErrorsException：该配置是只读的。

 配置myConfiguration = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration（〜）;
    myConfiguration.ConnectionStrings.ConnectionStrings（myDatabaseName）的ConnectionString = txtConnectionString.Text。
    myConfiguration.AppSettings.Settings.Item（的myKey）值= txtmyKey.Text。
    myConfiguration.Save（）;
 

编号：http://www.beansoftware.com/ASP.NET-Tutorials/Modify-Web.Config-Run-Time.aspx

Is it possible to change the ConnectionString value in a app.config at runtime? According to the MSDN documentation it should be possible as the ConnectionString property "Gets or sets the connection string."

My code looks like this:

ConnectionStringSettings mainConnection = ConfigurationManager.ConnectionStrings["mainConnection"];
mainConnection.ConnectionString = "Data Source=SERVER;Initial Catalog=" + NewDatabaseName + ";Integrated Security=True";

The error that I receive is this: "Unhandled Exception: System.Configuration.ConfigurationErrorsException: The configuration is read only."

Configuration myConfiguration = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("~"); 
    myConfiguration.ConnectionStrings.ConnectionStrings("myDatabaseName").ConnectionString = txtConnectionString.Text; 
    myConfiguration.AppSettings.Settings.Item("myKey").Value = txtmyKey.Text; 
    myConfiguration.Save(); 

Ref: http://www.beansoftware.com/ASP.NET-Tutorials/Modify-Web.Config-Run-Time.aspx