2008年3月28日
面试常用代码
最好背下来
1.取配置节数据库连接信息
            string connstring = string.Empty;
            ConnectionStringSettings settings = ConfigurationManager.ConnectionStrings["DataBaseConnection"];
            if (settings != null)
            {
                connstring = settings.ConnectionString;
            }

2 .操作数据库
        public DataSet ExecuteDataSet(string sql, string connectionString)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                DataSet ds = new DataSet();
                SqlDataAdapter da = new SqlDataAdapter(sql, connectionString);
                da.Fill(ds);
                return ds;
            }
        }

        public int ExecuteNonQuery(string sql, string connectionString)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
                SqlCommand cmd = new SqlCommand(sql, connection);

                return cmd.ExecuteNonQuery();
            }
        }

        public object ExecuteScalar(string sql, string connectionString)
        {
            using (SqlConnection connection = new SqlConnection(connectionString))
            {
                connection.Open();
                SqlCommand cmd = new SqlCommand(sql, connection);

                return cmd.ExecuteScalar();
            }
        }

3.修改配置信息
        public void SaveConfig(string key, string value)
        {
            try
            {
                string fileName = "Web.Config";
                XmlDocument document = new XmlDocument();
                document.Load(fileName);
                ((XmlElement)document.SelectSingleNode(@"//AppSetting/add[@key='" + key + "']")).SetAttribute("Value", value);
                document.Save(fileName);
            }
            catch (Exception ex)
            {
                throw new Exception(ex.Message);
            }
        }
注意,使用了XPATH查询相关结点
posted @ 2008-03-28 11:38 CSST SOFT STUDIO LOG 阅读(275) 评论(2) 编辑