How to Store and Retrieve File in SQL Server Database using C# .Net

Store/Insert File into SQL Server Database as Binary datatype

 We are doing two processes to store/save file into SQL Server table.
      i. Convert file content into Byte Array(Byte [])
      ii. Insert file content’s Byte Array into Sql Server

Consider the text file sample.txt.

public static void InsertFileintoSqlDatabase()
{
    string filePath = @"C:\sample.txt";

    using (SqlConnection sqlconnection = new SqlConnection(@"Data Source=.SQLExpress; 
Initial Catalog=MorganDB; Integrated Security=SSPI;"))
    {
        sqlconnection.Open();

        // create table if not exists 
        string createTableQuery = @"Create Table [MyTable](ID int, [FileData] varbinary(max))";
        SqlCommand command = new SqlCommand(createTableQuery, sqlconnection);
        command.ExecuteNonQuery();

        // Converts text file(.txt) into byte[]
        byte[] fileData = File.ReadAllBytes(filePath);

        string insertQuery = @"Insert Into [MyTable] (ID,[FileData]) Values(1,@FileData)";

        // Insert text file Value into Sql Table by SqlParameter
        SqlCommand insertCommand = new SqlCommand(insertQuery, sqlconnection);
        SqlParameter sqlParam = insertCommand.Parameters.AddWithValue("@FileData", fileData);
        sqlParam.DbType = DbType.Binary;
        insertCommand.ExecuteNonQuery();
    }
}

Retrieve/Read/Export File from SQL Server Database 

Use the below C# code to export/read/retrieve text file from SQL Server table that was stored as binary type and to save/export as new text file.

public static void ExportFileFromSqlDatabase(int ID)
        {
            using (SqlConnection sqlconnection = new SqlConnection(@"Data Source=.SQLExpress; 
Initial Catalog=MorganDB; Integrated Security=SSPI;"))
            {
                sqlconnection.Open();

                string selectQuery = string.Format(@"Select [FileData] From [MyTable] Where ID={0}"
                                    , ID);

                // Read File content from Sql Table 
                SqlCommand selectCommand = new SqlCommand(selectQuery, sqlconnection);
                SqlDataReader reader = selectCommand.ExecuteReader();
                if (reader.Read())
                {
                    byte[] fileData = (byte[])reader[0];
                    // Write/Export File content into new text file
                    File.WriteAllBytes(@"C:\New_Sample.txt", fileData);
                }
            }
        }