Get variable for two clicks on form - vb.net

Question

I am trying to assign two clicks to two variables on my Mouse_Down event on my form. Here is the starting code I am working with on Mouse_Down event. What I am trying to do is click two points on a form, get the X & Y location (these will then give me my button size). Example: First Click get X & Y, Second Click get X & Y then perform click of a button.... repeat this until I quit.
Private Sub Form1_MouseDown(sender As Object, e As MouseEventArgs) Handles MyBase.MouseDown
Dim XYClickOne, XYClickTwo
Dim count As Integer
count = 0
Do
XYClickOne = e.X & "," & e.Y
XYClickTwo = e.X & "," & e.Y
count = count + 1
Loop Until count = 2
Button1.PerformClick() 'After 2nd click, create button.
End Sub

Answer 1

Move those variables out to Form level so they are accessible by other methods, and will persist across clicks. Here's a quick example:
Public Class Form1
Private points(2) As Point
Private count As Integer = 0
Private Sub Form1_MouseDown(sender As Object, e As MouseEventArgs) Handles Me.MouseDown
If e.Button = MouseButtons.Left Then
points(count) = New Point(e.X, e.Y)
count = count + 1
If count = 2 Then
count = 0
CreateButton(points(0), points(1))
End If
End If
End Sub
Private Sub CreateButton(ByVal ptA As Point, ByVal ptB As Point)
Dim pt As New Point(Math.Min(ptA.X, ptB.X), Math.Min(ptA.Y, ptB.Y))
Dim sz As New Size(Math.Abs(ptA.X - ptB.X) + 1, Math.Abs(ptA.Y - ptB.Y) + 1)
Dim btn As New Button
btn.Bounds = New Rectangle(pt, sz)
btn.Text = "X"
Me.Controls.Add(btn)
End Sub
End Class

Answer 2

Thought you might like a quick example of making a "rubber band selection". Click and DRAG on your form with the left mouse button:
The artifacts are from my screen recorder, in reality it drew smoothly with out leaving lines behind:
Code:
Public Class Form1
Private ptA, ptB As Point
Private count As Integer = 0
Private firstBoxDrawn As Boolean = False
Private Sub Form1_MouseDown(sender As Object, e As MouseEventArgs) Handles Me.MouseDown
If e.Button = MouseButtons.Left Then
ptA = Me.PointToScreen(New Point(e.X, e.Y))
ptB = ptA
firstBoxDrawn = False
End If
End Sub
Private Sub Form1_MouseMove(sender As Object, e As MouseEventArgs) Handles Me.MouseMove
If e.Button = MouseButtons.Left Then
If firstBoxDrawn Then
' erase the previous box by drawing it again
ControlPaint.DrawReversibleFrame(RectangleFromPoints(ptA, ptB), Color.Black, FrameStyle.Dashed)
End If
ptB = Me.PointToScreen(New Point(e.X, e.Y))
' draw the new box
ControlPaint.DrawReversibleFrame(RectangleFromPoints(ptA, ptB), Color.Black, FrameStyle.Dashed)
firstBoxDrawn = True
End If
End Sub
Private Sub Form1_MouseUp(sender As Object, e As MouseEventArgs) Handles Me.MouseUp
If e.Button = MouseButtons.Left Then
' erase the box
ControlPaint.DrawReversibleFrame(RectangleFromPoints(ptA, ptB), Color.Black, FrameStyle.Dashed)
CreateButton(Me.PointToClient(ptA), Me.PointToClient(ptB))
End If
End Sub
Private Sub CreateButton(ByVal ptA As Point, ByVal ptB As Point)
Dim btn As New Button
btn.Text = "X"
btn.Bounds = RectangleFromPoints(ptA, ptB)
Me.Controls.Add(btn)
End Sub
Private Function RectangleFromPoints(ByVal ptA As Point, ByVal ptB As Point) As Rectangle
Dim pt As New Point(Math.Min(ptA.X, ptB.X), Math.Min(ptA.Y, ptB.Y))
Dim sz As New Size(Math.Abs(ptA.X - ptB.X) + 1, Math.Abs(ptA.Y - ptB.Y) + 1)
Return New Rectangle(pt, sz)
End Function
End Class