从SQL Server VarBinary（Max）读取图像

Question

I have a SQL Server Database. I have stored an image in there which is a varbinary(max). I inserted the image the following way :

string consString = ConfigurationManager.ConnectionStrings["connection"].ConnectionString;
            SqlConnection con = new SqlConnection(consString);
            con.Open();

            String filePath = fuImage.PostedFile.FileName;
            String naam = Path.GetFileName(filePath);
            String extension = Path.GetExtension(naam);

            Stream stream = fuImage.PostedFile.InputStream;
            BinaryReader br = new BinaryReader(stream);
            Byte[] imgByte = br.ReadBytes((Int32)stream.Length);


            SqlCommand cmd = new SqlCommand();
            cmd.CommandType = CommandType.StoredProcedure;
            cmd.CommandText = "spAddImage";
            cmd.Parameters.AddWithValue("@FOTO", imgByte);
            cmd.Parameters.AddWithValue("@ARTIEST", ddlArtiest.SelectedValue);
            cmd.Connection = con;
            cmd.ExecuteNonQuery();
            con.Close();

The image now looks like this in the database : It is stored as a varbinary.

http://puu.sh/ikF83/6a03b52520.png <--- database

Now I want to display my image on my asp.net page that I have inserted.

But I have no idea how I can achieve this.

Answer 1

You could use SqlDataReader to go over the results and get back what you need

var reader = cmd.ExecuteReader();
while (reader.Read())
{
  byte[] myImage = (byte[])reader["MyImageColumn"];
}

This is from top of my head so make your adjustments as required. But it should give you the basic idea.

Furthermore, It's strongly recommended to use the using block as it ensures the object is disposed correctly.

So you could change your code to

using(var connection = new SqlConnection(connectionString))
{
  //Your command 
  connection.Open();

  //Datareader here

}//Object disposed here

Reference to SqlDataReader

Reference to using block

Answer 2

Extending the answer provided by Izzy, below is how we have implemented the same.

public HttpResponseMessage RenderImage(RenderRequest renderRequest, HttpRequestMessage request)
{
    var httpResponse = new HttpResponseMessage();

    try
    {
        var reader = cmd.ExecuteReader();
        while (reader.Read())
        {
            byte[] imagebytes = (byte[])reader["MyImageColumn"];
        }

        return httpResponse = request.CreateResponse<byte[]>(HttpStatusCode.OK, imagebytes, new ImageMediaFormatter("image/png"));
    }
    catch ()
    {
        throw;
    }
}