ASP.NET SQLServer2005 数据库备份与还原

using System;
using System.Data.SqlClient;
using System.Data;
using System.IO;

namespace NET.Common
{
    /// <summary>
    /// 数据库操作帮助类
    /// </summary>
    public class DatabaseHelper
    {
        private const string SQL_DATABASE_BACK = "BACKUP DATABASE {0} TO DISK = '{1}'"; //数据库备份语句
        private const string SQL_DATABASE_RESTORE = "RESTORE DATABASE {0} FROM DISK = '{1}' WITH REPLACE"; //数据库还原语句
        private const string SQL_SELECT_ALL_CONN = "SELECT spid FROM master..sysprocesses WHERE dbid=db_id('{0}')"; //获取指定数据库所有链接语句

        /// <summary>
        /// 实例数据库操作
        /// </summary>
        /// <param name="masterConnectionString">master数据库链接字符串</param>
        public DatabaseHelper(string masterConnectionString)
        {
            this.MasterConnectionString = masterConnectionString;
        }

        /// <summary>
        /// master数据库链接字符串
        /// </summary>
        private string MasterConnectionString { get; set; }

        /// <summary>
        /// SQLServer数据库备份
        /// </summary>
        /// <param name="connectionString">数据库连接字符串</param>
        /// <param name="backName">备份文件名称，不包含后缀名</param>
        /// <param name="path">备份文件存放的物理路径</param>
        public bool Back(string dbName, string backName, string path)
        {
            //判断存放备份文件的目录是否存在
            if (!Directory.Exists(path))
            {
                //不存在，新建目录
                Directory.CreateDirectory(path);
            }

            try
            {
                using (SqlConnection conn = new SqlConnection(MasterConnectionString))
                {
                    //设置存放备份文件的完整物理路径
                    string backPath = path + "\\" + backName + ".bak";

                    //设置数据库备份的T-SQL语句
                    string t_sql_back = string.Format(SQL_DATABASE_BACK, dbName, backPath);

                    using (SqlCommand cmd = new SqlCommand(t_sql_back, conn))
                    {
                        cmd.CommandType = CommandType.Text;
                        conn.Open();

                        //开始备份
                        cmd.ExecuteNonQuery();

                        return true;
                    }
                }
            }
            catch
            {
                return false;
            }
        }

        /// <summary>
        /// SQLServer数据库还原
        /// </summary>
        /// <param name="dbName">要进行还原的数据库名称</param>
        /// <param name="fullPath">备份文件的完整物理路径</param>
        public bool Restore(string dbName, string fullPath)
        {
            //判断还原使用的文件是否存在
            if (!File.Exists(fullPath))
            {
                return false;
            }

            try
            {
                using (SqlConnection conn = new SqlConnection(MasterConnectionString))
                {
                    //设置数据库还原的T-SQL语句
                    string t_sql_restore = string.Format(SQL_DATABASE_RESTORE, dbName, fullPath);

                    //设置查询指定数据库的所有连接
                    string t_sql_select_all_conn = string.Format(SQL_SELECT_ALL_CONN, dbName);

                    string t_sql_kill;

                    conn.Open();

                    //获取指定数据库所有连接
                    SqlCommand cmd = new SqlCommand(t_sql_select_all_conn, conn);
                    SqlDataAdapter reSDA = new SqlDataAdapter(cmd);
                    DataTable dtConn = new DataTable();
                    reSDA.Fill(dtConn);

                    //逐一删除连接
                    for (int i = 0; i < dtConn.Rows.Count; i++)
                    {
                        t_sql_kill = " kill  " + dtConn.Rows[i][0].ToString();
                        cmd = new SqlCommand(t_sql_kill, conn);
                        cmd.ExecuteNonQuery();
                    }

                    //执行还原操作
                    cmd = new SqlCommand(t_sql_restore, conn);
                    cmd.ExecuteNonQuery();

                    //清空当前连接池，这个很主要，如果不清空还原后第一次访问会出现“在向服务器发送请求时发生传输级错误。 (provider: 共享内存提供程序, error: 0 - 管道的另一端上无任何进程。)”错误
                    SqlConnection.ClearPool(conn);
                    return true;
                }

            }
            catch
            {
                return false;
            }
        }
    }
}