Everything I have found shows how to add a row to a database for new images...

I am trying to update an existing row with a longblob field to store a logo and cannot seem to grasp what to do

Any help would be greatly appreciated

Take a look at this thread:
http://www.daniweb.com/forums/thread247583.html

MeSampath provided this code:

MySqlConnection mcon = null;
MySqlCommand cmd = null;
FileStream fsObj = null;
BinaryReader binRdr = null;
try
{
 //converting image to bytes
 fsObj = File.OpenRead(pictureBox1.ImageLocation);
 byte[] imgContent = new byte[fsObj.Length];
 binRdr = new BinaryReader(fsObj);
 imgContent = binRdr.ReadBytes((int)fsObj.Length);
 mcon = new MySqlConnection("server=localhost;user=root;pwd=root;database=test;");
 mcon.Open();
 
 //inserting into MySQL db
 cmd = new MySqlCommand("insert into users  (userid,username,userphoto) values (@userid, @username,  @userphoto)", mcon);
 cmd.Parameters.Add(new MySqlParameter("@userid",  (object)textBox1.Text));
 cmd.Parameters.Add(new MySqlParameter("@username",  (object)textBox2.Text));
 cmd.Parameters.Add(new MySqlParameter("@userphoto",  (object)imgContent));
 MessageBox.Show(cmd.ExecuteNonQuery().ToString() + " rows  affected");
}
catch (MySqlException mex)
{
 MessageBox.Show(mex.Message);
}
finally
{
 if (binRdr != null)binRdr.Close();
 binRdr = null;

 if (fsObj != null)fsObj.Close();
 fsObj = null;
  
 if (cmd != null)cmd.Dispose();
 cmd = null;

 if (mcon != null)
 {
  if (mcon.State == ConnectionState.Open)
  mcon.Close();
 } 
}

That code inserts a new image. You can change the INSERT query to an UPDATE query to modify an existing image:

MySqlConnection mcon = null;
MySqlCommand cmd = null;
FileStream fsObj = null;
BinaryReader binRdr = null;
try
{
 //converting image to bytes
 fsObj = File.OpenRead(pictureBox1.ImageLocation);
 byte[] imgContent = new byte[fsObj.Length];
 binRdr = new BinaryReader(fsObj);
 imgContent = binRdr.ReadBytes((int)fsObj.Length);
 mcon = new MySqlConnection("server=localhost;user=root;pwd=root;database=test;");
 mcon.Open();
 
 //inserting into MySQL db
 //cmd = new MySqlCommand("insert into users  (userid,username,userphoto) values (@userid, @username,  @userphoto)", mcon);
 cmd = new MySqlCommand("update users set userphoto = @userphoto where userid = @userid", mcon);
 cmd.Parameters.Add(new MySqlParameter("@userid",  (object)textBox1.Text));
 //cmd.Parameters.Add(new MySqlParameter("@username",  (object)textBox2.Text));
 cmd.Parameters.Add(new MySqlParameter("@userphoto",  (object)imgContent));
 MessageBox.Show(cmd.ExecuteNonQuery().ToString() + " rows  affected");
}
catch (MySqlException mex)
{
 MessageBox.Show(mex.Message);
}
finally
{
 if (binRdr != null)binRdr.Close();
 binRdr = null;

 if (fsObj != null)fsObj.Close();
 fsObj = null;
  
 if (cmd != null)cmd.Dispose();
 cmd = null;

 if (mcon != null)
 {
  if (mcon.State == ConnectionState.Open)
  mcon.Close();
 } 
}
commented: When Scott speaks one should listen :) +2

As always Scott you are right on target...

I was having diffcultiies in wording the update statement and inserting the binary for the picture

Thank you again. Rep up to you.

using Windows 7 and calling:

OpenFileDialog LogoLoad = new OpenFileDialog();

            LogoLoad.InitialDirectory = Environment.GetFolderPath(Environment.SpecialFolder.MyPictures);
            LogoLoad.Filter = "Image Files|*.jpg;*.gif;*.bmp;*.png;*.jpeg|All Files|*.*";
            LogoLoad.Title = "Load Dealer Logo";
            LogoLoad.FilterIndex = 1;
            LogoLoad.RestoreDirectory = true;

            if (LogoLoad.ShowDialog() == DialogResult.OK)
            {
                filenname = Path.GetFileName(LogoLoad.FileName);
                path = Path.GetDirectoryName(LogoLoad.FileName);
                extension = Path.GetExtension(LogoLoad.FileName);

Problem is picturebox1.ImageLocation comes up as Null even though picture is displayed and path+filename does not give correct path IE..
It says c:\Users\username\Pictures\logo.gif
when it is actually c:\Users\username\My Pictures\Pictures\logo.gif

any clues here... cant wrap my mind why it would be giving wrong path yet displaying proper picture

Thank you for the help mate

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