C#

;
Socket socket;
IPEndPoint hostEndPoint;
string packet;
 
public void run()
{
  TCPConnect();

  packet = SendReceive("/signin.aspx", "GET");
  if (GetReturnCode(packet) == "400")
    TCPReset();

  packet = SendReceive("/index.html", "GET");

  TCPClose();  
}
 
private void TCPConnect()
{
  // Make sure there is a connection
  if (socket == null)
  {
    socket = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
    hostEndPoint = new IPEndPoint(ipaddr, port);
  }

  socket.Connect(hostEndPoint);
}
 
// My problem is getting this function working properly
private void TCPReset()
{
  socket.Disconnect(true); // Close the socket connection and allow reuse of the socket
  socket.Connect(hostEndPoint); // This is ignored according to Ethereal,
                                // nothing is sent even using socket.Send()
}
 
private void TCPClose()
{
  socket.Shutdown(SocketShutdown.Both);
  socket.Close();
}
 
private string SendReceive(string strURI, strMethod)
{
  string pcAppend = " HTTP/1.1\r\nConnection: Keep-Alive\r\n\Content-Length: 0\r\n" +
      "User-Agent: Mozilla/4.0 (Compatible; MSIE 7.0; Windows NT 5.2; .NET CLR " +
      "2.0.50727; .NET CLR 3.0.04506.30; InfoPath.1; .NET CLR 3.5.21022)\r\n" +
      "Content-Type: application/x-www-form-urlencoded\r\nHost: " + strIPAddress + "\r\n\r\n";
  byte[] pcSend = System.Text.ASCIIEncoding.ASCII.GetBytes(strMethod + strURI + pcAppend);
  byte[] bfBuffer = new byte[10240];

  socket.Send(pcSend, pcSend.Length, 0);
  socket.Receive(bfBuffer, bfBuffer.Length, SocketFlags.None);

  return System.Text.ASCIIEncoding.ASCII.GetString(bfBuffer);
}

public class PictureBoxEx : ScrollableControl
    {
        private Image _image;
        private Single _zoom;
        private InterpolationMode _interpolationMode;
        private Point lastPos;        

        #region Properties

        [Category("Appearance"), Description("The image to be displayed.")]
        public Image Image
        {
            get { return _image; }
            set 
            { 
                _image = value;
                this.UpdateScaleFactor();
                this.Invalidate();
            }
        }

        [Category("Appearance"), Description("The zoom factor. Less than 1 to reduce. More than 1 to magnify.")]
        public Single Zoom
        {
            get { return _zoom; }
            set
            {
                _zoom = value;
                this.UpdateScaleFactor();
                this.Invalidate();
            }
        }

        [Category("Appearance"), Description("The interpolation mode used to smooth the drawing.")]
        public InterpolationMode InterpolationMode
        {
            get { return _interpolationMode; }
            set { _interpolationMode = value; }
        }

        public Point LastPosition
        {
            get { return lastPos; }
            set { lastPos = value; }
        }

        #endregion

        public PictureBoxEx()
        {
            this.SetStyle(ControlStyles.AllPaintingInWmPaint | ControlStyles.UserPaint | ControlStyles.ResizeRedraw | ControlStyles.UserPaint | ControlStyles.OptimizedDoubleBuffer, true);
            this.AutoScroll = true;
            this.Zoom = 1f;
        }

        private void UpdateScaleFactor()
        {
            if (this.Image == null)
                this.AutoScrollMargin = this.Size;
            else
                this.AutoScrollMinSize = new Size(Convert.ToInt32(this.Image.Width * this.Zoom + .5f), Convert.ToInt32(this.Image.Height * this.Zoom + .5f));
        }

        protected override void OnPaintBackground(PaintEventArgs e)
        {
            // Do nothing
        }

        protected override void OnPaint(PaintEventArgs e)
        {
            if (this.Image == null)
            {
                this.OnPaintBackground(e);
                return;
            }
            Matrix mx = new Matrix(this.Zoom, 0, 0, this.Zoom, 0, 0);
            mx.Translate(this.AutoScrollPosition.X / this.Zoom, this.AutoScrollPosition.Y / this.Zoom);
            e.Graphics.Transform = mx;
            e.Graphics.InterpolationMode = this.InterpolationMode;
            e.Graphics.DrawImage(this.Image, new Rectangle(0, 0, this.Image.Width, this.Image.Height), 0, 0, this.Image.Width, this.Image.Height, GraphicsUnit.Pixel);
            base.OnPaint(e);
        }        
    }

private void buttonSaveXML_Click(object sender, EventArgs e)
{
    // DB1: Read table1 in DataSet and write in XML-File: works OK
    OleDbConnection conn = new OleDbConnection
        ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=TestDataTable.mdb;");
    conn.Open();
    DataSet ds = new DataSet("test-DS");
    OleDbDataAdapter da = new OleDbDataAdapter("select keycol, col1, col2 from table1", conn);
    da.Fill(ds, "table1");
    ds.WriteXml("test-DS.xml", XmlWriteMode.WriteSchema);
    conn.Close();
    // 2 rows of Data in columns   keycol, col1, col2   with values:
    // row1     col1row1    col2row1
    // row2     col1row2    col2row2
}

private void buttonReadXML_Click(object sender, EventArgs e)
{
    // !!!! To simulate the second DB: Database has changed: row1 is deleted. col1row2 has changed its value. !!!!
    // This should restore table1 to original values (insert row1, update row2)
    // Read DS from XML-File.
    OleDbConnection conn = new OleDbConnection
        ("Provider=Microsoft.Jet.OLEDB.4.0;Data Source=TestDataTable.mdb;");
    conn.Open();
    DataSet ds = new DataSet("test-DS");
    ds.ReadXml("test-DS.xml", XmlReadMode.ReadSchema);
    // use DataAdapter to do the whole work
    OleDbDataAdapter da = new OleDbDataAdapter("select keycol, col1, col2 from table1", conn);
    da.ContinueUpdateOnError = true; // no break on error (e.g. row with same key-value)
    OleDbCommandBuilder cb = new OleDbCommandBuilder(da);
    cb.ConflictOption = ConflictOption.OverwriteChanges; // Update changes of non-key columns
    DataTable dt = ds.Tables["table1"];

    ////////////////////////
    // first Update(): because all datarows have RowState ADDED, this inserts row1
    // row2 leads to error, because key row2 exists (but still is OK!)
    string trace_command = cb.GetInsertCommand(true).CommandText;
    // INSERT INTO table1 (keycol, col1, col2) VALUES (?, ?, ?)
    int updcount = da.Update(dt);  // does one INSERT
    MessageBox.Show("first da.Update() does INSERT on " + updcount.ToString() + " rows.\n" +
        "InsertCommand is: " + trace_command);
    for (int index = dt.Rows.Count - 1; index >= 0; index--)
        if (!dt.Rows[index].HasErrors)
            dt.Rows.Remove(dt.Rows[index]); // if no error in row: it was inserted, so remove it

    ////////////////////////
    // second Update(): intension is to update col1 in row2
    dt.AcceptChanges();     // datarows: RowState was ADDED, now UNCHANGED
                            // SetModified causes exception, if RowState is ADDED
    foreach (DataRow dr in dt.Rows)
        dr.SetModified();   // now: dr.RowState is MODIFIED. ==> should invoke UPDATE
    trace_command = cb.GetUpdateCommand(true).CommandText;
    // UPDATE table1 SET keycol = ?, col1 = ?, col2 = ? WHERE ((keycol = ?))
    updcount = da.Update(dt);
    MessageBox.Show("second da.Update() on " + updcount.ToString() + " rows.\n" +
        "UpdateCommand is: " + trace_command);
    // This does 1 Update, but the col1row2 value is NOT updated!!!
    // This is the problem: it seems that the UPDATE-Command only updates "changed" values!
    // But how to tell the DataRow.Item, that it has changed????

    ////////////////////////
    // What i did, to mark the item as changed: save, change and restore the value!
    // But I think, there are better ways to do this???
    dt.AcceptChanges();
    foreach (DataRow dr in dt.Rows)
    {
        string save = dr["col1"].ToString();
        dr["col1"] = "new changed value";
        dr.AcceptChanges();
        dr["col1"] = save;
    }
    updcount = da.Update(dt);

    conn.Close();
}

SharpDevelop is participating in the Google Summer of Code this year.

It is an opportunity for students to earn 4500 USD over the summer by working on an open-source project.

We have created a list of ideas, but you can work basically on anything you want as long as it is relevant to SharpDevelop.  You can find the list of ideas and any further information on the SharpDevelop wiki page for the Google Summer of Code.  You can submit your application here.

If you are not a student or if you do not have enough spare time, you can benefit as well.... share your ideas with us and maybe some student will pick them up and implement them.

Feel free to contact us on the forums or via email.

Please spread the word and tell your friends about the Summer of Code...