向sqlite数据库写入文件流问题

Question

请教怎么在C#中向sqlite数据库保存文件，比如我要上传一个*.xls文件到sqlite表里，该如何实现？

Answer 1

Sqlite数据库里指定数据类型为:Blob。在数据访问指定参数类型为:DbType.Binary然后把Excel文件读到字节数组里。        using(FileStream file = File.Open(this.TextBox2.Text,FileMode.Open))
        {        
            byte[] bytes = new byte[file.Length];
            file.Read(bytes, 0, Convert.ToInt32(file.Length));
            testDal.Insert(Guid.NewGuid().ToString(), bytes, null);
        }数据访问存储字节数据。
public Int32 Insert(string ID,Byte[] fileStream, SQLiteTransaction trans)
        {
            if (conn.State == ConnectionState.Closed)
            {
                conn.Open();
            }
            SQLiteCommand command;
            if (trans == null)
            {
                command = new SQLiteCommand("insert into test(ID,excelText) values (:ID,:excelText)", conn);
            }
            else
            {
                command = new SQLiteCommand("insert into test(ID,excelText) values (:ID,:excelText)", conn, trans);
            }
            command.Parameters.Add("ID", DbType.String);
            command.Parameters.Add("excelText", DbType.Binary);            command.Parameters["ID"].Value = ID;
            command.Parameters["excelText"].Value = fileStream;
            try
            {
                return command.ExecuteNonQuery();
            }
            catch
            {
                return 0;
            }
        }
根据主键返回Excel的字节数据
        public byte[] GetExcel(string ID)
        {
            if (conn.State == ConnectionState.Closed)
            {
                conn.Open();
            }
            SQLiteCommand command = new SQLiteCommand("Select excelText from test where ID = :ID", conn);
            command.Parameters.Add("ID", DbType.String);
            command.Parameters["ID"].Value = ID;            SQLiteDataReader dr = null;            dr = command.ExecuteReader();            byte[] File = null;
            if (dr.Read())
            {
                File = (byte[])dr[0];
            }
            return File;
        }把字节数据存储为文件
        using (FileStream fs = File.Create("D:\\Test.xls"))
        {
            fs.Write(file, 0, file.Length);
            fs.Close();
        }