爲web.config寫入數據庫連接字符串的方法

1.寫入連接字符串

protected void Page_Load(object sender, EventArgs e)
      {
          if (!Page.IsPostBack)
          {
            
              // Create a new ConnectionStringSettings object and populate it
              ConnectionStringSettings conn = new ConnectionStringSettings();
              conn.ConnectionString =
                   "Server=localhost;User ID=sa;Password=123456; " +
                   "Database=Northwind;Persist Security Info=True";
              conn.Name = "AppConnectionString2";
              conn.ProviderName = "System.Data.SqlClient";

              // Add the new connection string to the web.config
              Configuration config = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("example");
              config.ConnectionStrings.ConnectionStrings.Add(conn);
              config.Save();
          }
      }
2.修改連接字符串

protected void Page_Load(object sender, EventArgs e)
      {
          // Retrieve an existing connection string into a Connection String Builder
          System.Data.SqlClient.SqlConnectionStringBuilder builder = new
              System.Data.SqlClient.SqlConnectionStringBuilder();

          // Change the connection string properties
          builder.DataSource = "localhost";
          builder.InitialCatalog = "Northwind1";
          builder.UserID = "sa";
          builder.Password = "password";
          builder.PersistSecurityInfo = true;

          // Save the connection string back to the web.config
          Configuration config = System.Web.Configuration.WebConfigurationManager.OpenWebConfiguration("/Chapter11");
          config.ConnectionStrings.ConnectionStrings["AppConnectionString1"].ConnectionString =
              builder.ConnectionString;
          config.Save();
      }