Public Class Form1

    Private mouseOffset As Point
    Private isMouseDown As Boolean = False
    Private Sub Form1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseDown
        Dim xOffset As Integer
        Dim yOffset As Integer
        If e.Button = Windows.Forms.MouseButtons.Left Then
            xOffset = -e.X - SystemInformation.FrameBorderSize.Width
            yOffset = -e.Y - SystemInformation.CaptionHeight - _
             SystemInformation.FrameBorderSize.Height
            mouseOffset = New Point(xOffset, yOffset)
            isMouseDown = True
        End If
    End Sub
    Private Sub Form1_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseMove
        If isMouseDown Then
            Dim mousePos As Point = Control.MousePosition
            mousePos.Offset(mouseOffset.X, mouseOffset.Y)
            Location = mousePos
        End If
    End Sub
    Private Sub Form1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles Me.MouseUp
        ' Changes the isMouseDown field so that the form does
        ' not move unless the user is pressing the left mouse button.
        If e.Button = Windows.Forms.MouseButtons.Left Then
            isMouseDown = False
        End If
    End Sub

End Class