Private Sub Form1_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load
    TextBox1.ContextMenu = New ContextMenu()
End Sub

Private Sub TextBox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles TextBox1.MouseDown
    If (e.Button = Windows.Forms.MouseButtons.Right) Then
        TextBox1.Select(0, TextBox1.Text.Length)
    End If
End Sub

private void Form1_Load(object sender, EventArgs e)
{
    // This line suppresses the default context menu for the TextBox control. 
    textBox1.ContextMenu = new ContextMenu();
    textBox1.MouseDown += new MouseEventHandler(textBox1_MouseDown);
}

void textBox1_MouseDown(object sender, System.Windows.Forms.MouseEventArgs e)
{
    if (e.Button == MouseButtons.Right)
    {
        textBox1.Select(0, textBox1.Text.Length);
    }
}

Dim FirstPoint As Point
Dim HaveFirstPoint As Boolean = False

Private Sub Form1_MouseDownDrawing(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown
    If HaveFirstPoint Then
        Dim g As Graphics = Me.CreateGraphics()
        g.DrawLine(Pens.Black, FirstPoint, e.Location)
        HaveFirstPoint = False
    Else
        FirstPoint = e.Location
        HaveFirstPoint = True
    End If
End Sub

Point firstPoint;
Boolean haveFirstPoint;

public void EnableDrawing()
{
    this.MouseDown += new MouseEventHandler(Form1_MouseDownDrawing);
}

void Form1_MouseDownDrawing(object sender, System.Windows.Forms.MouseEventArgs e)
{
    if (haveFirstPoint)
    {
        Graphics g = this.CreateGraphics();
        g.DrawLine(Pens.Black, firstPoint, e.Location);
        haveFirstPoint = false;
    }
    else
    {
        firstPoint = e.Location;
        haveFirstPoint = true;
    }
}

Dim TrackTip As ToolTip

Private Sub TrackCoordinates()
    TrackTip = New ToolTip()
End Sub

Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseMove
    Dim TipText As String = String.Format("({0}, {1})", e.X, e.Y)
    TrackTip.Show(TipText, Me, e.Location)
End Sub

ToolTip trackTip;

private void TrackCoordinates()
{
    trackTip = new ToolTip();
    this.MouseMove += new MouseEventHandler(Form1_MouseMove);
}

void Form1_MouseMove(object sender, System.Windows.Forms.MouseEventArgs e)
{
    String tipText = String.Format("({0}, {1})", e.X, e.Y);
    trackTip.Show(tipText, this, e.Location);
}