Multi Selection in PictureBox

[yuzhen]

hi,

I'm currently working on multi selection on the Picturebox. I'm kinda of stuck with these coding. can anyone pls help me. thks.

Public Class Page_2
[COLOR="seagreen"]' for selection on part of body[/COLOR]
    Private start As Point = Point.Empty
    Private rect() As Rectangle
    Private p As Pen
    Dim CurSel As String [COLOR="seagreen"](what shld i DIM it as??)[/COLOR]

Private Sub Page_2_Load(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.Load

        'initialize pen
        p = New Pen(Color.Black)
        p.DashStyle = Drawing2D.DashStyle.Dash

    End Sub

Private Sub pbBody_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles pbBody.MouseDown


        start = e.Location

    End Sub

    Private Sub pbBody_MouseMove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles pbBody.MouseMove

        If start <> Point.Empty Then
            Dim x As Integer = Math.Min(start.X, e.X)
            Dim y As Integer = Math.Min(start.Y, e.Y)
            Dim wid As Integer = Math.Abs(start.X - e.X)
            Dim hgt As Integer = Math.Abs(start.Y - e.Y)
            Dim changefilter As Integer = 5
            If Math.Abs(x - wid) > changefilter _
              OrElse Math.Abs(y - Height) > changefilter Then
                CurSel += 1 ' Increase counter
                [COLOR="seagreen"]' Redim the array[/COLOR]
                ReDim Preserve rect(CurSel)
                rect(CurSel) = New Rectangle(x, y, wid, hgt)
                [COLOR="seagreen"]' At this point you may call PackData function to see if the new selection data "fits".
                ' If it doesn't, "rollback" this new item.
                ' A better way may be to "disable" selection feature if the user has made too many selections[/COLOR]                
            pbBody.Refresh()
            End If
        End If
    End Sub


    Private Sub pbBody_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles pbBody.MouseUp

        start = Point.Empty

    End Sub

    Private Sub pbBody_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles pbBody.Paint
        ReDim Preserve rect(CurSel)
        If rect(CurSel) <> Rectangle.Empty Then e.Graphics.DrawRectangle(p, rect(CurSel))

    End Sub

    Private Sub menuUndo_Click(ByVal sender As Object, ByVal e As System.EventArgs) Handles menuUndo.Click

        If CurSel >= 0 Then
            rect(CurSel) = Rectangle.Empty
            If CurSel >= 0 Then
                [COLOR="seagreen"]' Redim the array, can't redim to a negative size![/COLOR]
                ReDim Preserve rect(CurSel)
            End If
            pbBody.Refresh()
        End If

    End Sub

End Class

Attached is how it shld work

Best Regards,
Dawn.Lee

 

[jmcilhinney]

Each of those is just a rectangle drawn on the control with a specific type of pen. [ame="http://www.vbforums.com/showthread.php?t=426684"]Read this[/ame] to see how to draw multiple lines on a PictureBox. Given that each line has a bounding rectangle, it should be fairly easy to adapt that to draw rectangles instead.