sqlite 保存 二进制数据 武胜

in C#:

class Program
{
    static void Main(string[] args){if(File.Exists("test.db3")){File.Delete("test.db3");}using(var connection = new SQLiteConnection("Data Source=test.db3;Version=3"))using(var command = new SQLiteCommand("CREATE TABLE PHOTOS(ID INTEGER PRIMARY KEY AUTOINCREMENT, PHOTO BLOB)", connection)){
            connection.Open();
            command.ExecuteNonQuery();

            byte[] photo = new byte[]{1,2,3,4,5};

            command.CommandText ="INSERT INTO PHOTOS (PHOTO) VALUES (@photo)";
            command.Parameters.Add("@photo", DbType.Binary,20).Value = photo;
            command.ExecuteNonQuery();

            command.CommandText ="SELECT PHOTO FROM PHOTOS WHERE ID = 1";using(var reader = command.ExecuteReader()){while(reader.Read()){
                    byte[] buffer = GetBytes(reader);}}}}

    static byte[] GetBytes(SQLiteDataReader reader){
        const int CHUNK_SIZE =2*1024;
        byte[] buffer = new byte[CHUNK_SIZE];
        long bytesRead;
        long fieldOffset =0;using(MemoryStream stream = new MemoryStream()){while((bytesRead = reader.GetBytes(0, fieldOffset, buffer,0, buffer.Length))>0){
                stream.Write(buffer,0,(int)bytesRead);
                fieldOffset += bytesRead;}return stream.ToArray();}}}