Line Help

[sandezco]

I am working a problem VB-2005 and I am a little confused. If I used the following, I can draw lines. But if I try to use what lesson calls for I cannot draw lines.
graphicsObject.DrawLine(New Pen(Color.Black), _
e.X, e.Y, DIAMETER, DIAMETER)

Versus

graphicsObject.DrawLine(New Pen(Color.Black), _
x1, y1, x2, y2)
is this because I used the following statement ealier in the program?

' set diameter of MouseDown line
Private Const DIAMETER As Integer = 8

[Killer42]

You haven't made it clear which one works, and which doesn't. Or what happens when it doesn't work.

[CyberSoftHari]

You never point which event you are coding this and what is the value of x1,y1 and x2,y2!
Is it x1,y1 and x2,y2 are constant or following the mouse pointer?

[sandezco]

graphicsObject.DrawLine(New Pen(Color.Black), _
e.X, e.Y, DIAMETER, DIAMETER)

This one works (and it is following the mouse) my eventual goal is going to be to calculate the distance between end points of this line.

[CyberSoftHari]

First post what you did in your code and describe about your problem in detail. (Do not simply post 2 or 3 line of code.)

[sandezco]

First post what you did in your code and describe about your problem in detail. (Do not simply post 2 or 3 line of code.)

Here is what I have so far, most of it was based off of an example. I am suppose to use the following, but when I do I can not draw the line:

graphicsObject.DrawLine(New Pen(Color.Black), x1, y1, x2, y2)
 
Public Class LineLengthForm
 
    Dim x1 As Integer
    Dim x2 As Integer
    Dim y1 As Integer
    Dim y2 As Integer
 
    ' specify whether moving the mouse should erase
    Private shouldErase As Boolean = False
 
    ' specify whether moving the mouse should draw
    Private shouldDraw As Boolean = False
 
    ' set diameter of MouseDown line
    Private Const DIAMETER As Integer = 8
 
    ' create and initialize Graphics object
    Private graphicsObject As Graphics = CreateGraphics()
 
    ' handles LineLength's MouseDown event
    Private Sub LineLengthForm_MouseDown(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.MouseEventArgs) _
    Handles Me.MouseDown
 
        ' draw on Form if the left button is held down
        If e.Button = Windows.Forms.MouseButtons.Left Then
            shouldDraw = True
            ' erase black lines if right button is held down
        ElseIf e.Button = Windows.Forms.MouseButtons.Right Then
            shouldErase = True
        End If
    End Sub ' MouseDown
 
    ' handles LineLengthForm's MouseMove event
    Private Sub LineLengthForm_MouseMove(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.MouseEventArgs) _
    Handles Me.MouseMove
 
        ' draw line if mouse button is pressed
        If shouldDraw = True Then
            graphicsObject.DrawLine(New Pen(Color.Black), _
            e.X, e.Y, DIAMETER, DIAMETER)
            ' mouse pointer "erases" if right mouse button is pressed
        ElseIf shouldErase = True Then
            graphicsObject.DrawLine(New Pen(BackColor), _
            e.X, e.Y, DIAMETER, DIAMETER)
        End If
    End Sub 'LineLength_MouseMove
 
    ' handle LineLength's MouseUp event
    Private Sub LineLengthForm_MouseUp(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.MouseEventArgs) _
    Handles Me.MouseUp
 
        shouldDraw = False ' do not draw on the form
        shouldErase = False ' do not erase
    End Sub 'LineLength_MouseUp

[CyberSoftHari]

graphicsObject.DrawLine(New Pen(Color.Black), _
            e.X, e.Y, DIAMETER, DIAMETER)

here you have to change like

graphicsObject.DrawLine(New Pen(Color.Black), _
            X1, Y1, e.X, e.Y)

and in mouse down event

Private Sub LineLengthForm_MouseDown(ByVal sender As Object, _
    ByVal e As System.Windows.Forms.MouseEventArgs) _
    Handles Me.MouseDown
 
        ' draw on Form if the left button is held down
        If e.Button = Windows.Forms.MouseButtons.Left Then
            shouldDraw = True
            ' erase black lines if right button is held down
        ElseIf e.Button = Windows.Forms.MouseButtons.Right Then
            shouldErase = True
        End If
        X1 = e.X
        Y1 = e.Y
    End Sub ' MouseDown

and in mouse up X1 and Y1 to 0
and same thing apply to errase logic.
Note : This code will draw line to start and end point of mouse pointer. so it will not be a single line (it will look like shaded line, you don't draw a Straight line).

[sandezco]

Thanks for the insight!!!!!!!!!!!