将文件以二进制形式存储到Sql Server中

/DatSet读取文件/ #region /DatSet读取文件/
        /**//// <summary>
        /// 根据aaId,使用DataSet 读取**文件内容，还原恢复。
        /// </summary>
        /// <param name="ioId">**的ID号</param>
        /// <param name="tableName">表名</param>
        /// <param name="fieldName">存储**文件内容的字段</param>
        public bool ReadFileOutFormSqlServer(int ioId,string tableName,string fieldName)
        {
            bool flag=false;

            object tempfileName=null;

            string strSql="select fullpath,"+fieldName+" from "+tableName+" where infoID="+infoId;

            DataSet ds=new DataSet();
    
            Database database=new Database(p_sqlConnString);

            try
            {
                ds=database.DBDataSet(strSql);
            
                byte[] tmpFile=null;  
                foreach(DataRow dr in ds.Tables[0].Rows)
                {
                    if(dr[0]!=DBNull.Value)
                    {
                        tempfileName=dr[0];
                        tmpFile=(byte[])dr[1];
                    }
                }
                ds.Dispose();


                if(tmpFile!=null)
                {
                
                    string fileName=tempfileName.ToString();
                    FileInfo fi=new System.IO.FileInfo(fileName);
                    if(!fi.Exists)
                    {
                        //新建文件
                        using (FileStream fstream= fi.Create()) 
                        {
                            int length=tmpFile.Length;
                            fstream.Write(tmpFile,0,tmpFile.Length);
                            fstream.Close();
                            flag=true;
                        }

                    }
                    else
                    {
                        using(FileStream fs=fi.OpenWrite())
                        {
                            int length=tmpFile.Length;
                            fs.Write(tmpFile,0,tmpFile.Length);
                            fs.Close();
                            flag=true;
                        }
                    }
            
                }
            }
            catch (Exception err)
            {
                throw err;
            }
            finally
            {
                database.Close();
            }
            return flag;
        
        }

        #endregion

/***保存文件***/ #region /***保存文件***/
        /**//// <summary>
        /// 保存文件到SQL Server数据库中
        /// </summary>
        /// <param name="RRR">**文件类</param>
        /// <param name="tableName">表名</param>
        /// <param name="fieldName">存储**文件内容的字段</param>
        public bool SaveIntoSqlServer(RRR accredit,string tableName,string fieldName)
        {
            bool flag=false;
            //保存文件到SQL Server数据库中
            string fileName=accredit.FullPath;

            FileInfo fi=new FileInfo(fileName);
            if (fi.Exists)
            {
                SqlConnection cn=null;
                try
                {
                    byte[] dData=null;
            
                    //读文件，放入buffer
                    using(FileStream fs=fi.OpenRead())
                    {
                        dData=new byte[fi.Length];
                        int nReadLength=fs.Read(dData,0,(int)(fi.Length));

                    }
                    string sqlStr="insert into "+tableName+"(ioID,path,cTime,"+fieldName+") values("
                        +accredit.IoID+",'"+accredit.Path+"','"+accredit.CTime+"',@file)";

                    cn=ConnectToSqlSever();
                    if(cn.State==0) cn.Open();
                    SqlCommand cm=new SqlCommand(sqlStr,cn);
                    cm.Parameters.Add("@file",dData);
                    cm.ExecuteNonQuery();
                    cm.Dispose();
                    flag=true;
                }
                catch (Exception err)
                {
                    throw err;
                }
                finally
                {
                    cn.Close();
                }
            }
            return flag;
        }
        
        #endregion

数据字段为varbinary