private IDbConnection GetConnection()
    {
      switch(this.DbType)
      {
        case "SqlServer":
          return new System.Data.SqlClient.SqlConnection(this.ConntionString);
        case "Access":
                    string strProvider = "Provider=Microsoft.Jet.OLEDB.4.0;Data Source=";
                    strProvider +=  我想在这儿得到网站的物理路径 + this.ConntionString;          return new System.Data.OleDb.OleDbConnection(strProvider);
        default:
          return new System.Data.SqlClient.SqlConnection(this.ConntionString);
      }
    }