Visual Basic Power Pack - Select Line

Question

所以我使用Visual Basic Power Packs来做一些基本的简单图形。我有能力在我需要的地方画很多线，而且 VB 电源组允许我选择我画的实际线，但我不知道当我实际选择这些线时如何实现代码。

这是我的代码：

Imports Microsoft.VisualBasic.PowerPacks
Public Class Form1
    Dim ptA, ptB As Point                     ' starting and ending point
    Dim down = False
    Dim lines As New List(Of LineShape)
    Dim temp As LineShape                     ' temporary line to be drawn
    Dim canvas As New ShapeContainer          'shape container 
    Private Sub Form1_MouseDown(sender As Object, e As MouseEventArgs) Handles MyBase.MouseDown
        down = True
        canvas.Parent = Me
        temp = New LineShape
        temp.Parent = canvas
        ptA = New Point(e.X, e.Y)
        temp.StartPoint = ptA
        temp.EndPoint = ptA
    End Sub
    Private Sub Form1_MouseUp(sender As Object, e As MouseEventArgs) Handles MyBase.MouseUp
        down = False
        ptB = New Point(e.X, e.Y)
        lines.Add(temp)
        temp = Nothing
    End Sub
    Private Sub Form1_MouseMove(sender As Object, e As MouseEventArgs) Handles MyBase.MouseMove
        If down = True Then
            temp.X2 = e.X
            temp.Y2 = e.Y
        End If
    End Sub
End Class

当我运行并编译它时，每次我按住鼠标按钮，移动和释放时，我都可以画一条线。我可以选择这些行，我只是不知道如何添加代码，以便在我选择它时它会做一些事情。如果有人能帮助我，我将不胜感激。如果有人可以告诉我如何在单击一行及其起点和终点时显示消息框。

我正在创建一个结构分析程序，应该允许用户绘制建筑框架，然后单击线条并添加属性，例如它的材料等。

谢谢！！

京东

Answer 1

将点击处理程序添加到您的临时行...

Imports Microsoft.VisualBasic.PowerPacks
Public Class Form1
    Dim ptA, ptB As Point                     ' starting and ending point
    Dim down = False
    Dim lines As New List(Of LineShape)
    Dim temp As LineShape                     ' temporary line to be drawn
    Dim canvas As New ShapeContainer          'shape container 
    Private Sub Form1_MouseDown(sender As Object, e As MouseEventArgs) Handles MyBase.MouseDown
        down = True
        canvas.Parent = Me
        temp = New LineShape
        temp.Parent = canvas
        ptA = New Point(e.X, e.Y)
        temp.StartPoint = ptA
        temp.EndPoint = ptA
    End Sub
    Private Sub Form1_MouseUp(sender As Object, e As MouseEventArgs) Handles MyBase.MouseUp
        down = False
        ptB = New Point(e.X, e.Y)
        AddHandler temp.Click, AddressOf LineClickHandler
        lines.Add(temp)
        temp = Nothing
    End Sub
    Private Sub Form1_MouseMove(sender As Object, e As MouseEventArgs) Handles MyBase.MouseMove
        If down = True Then
            temp.X2 = e.X
            temp.Y2 = e.Y
        End If
    End Sub
    Private Sub LineClickHandler(sender As Object, e As MouseEventArgs)
        Dim MyLine As LineShape = DirectCast(sender, LineShape)
        MsgBox("Start = " & MyLine.StartPoint.ToString & " End Point = " & MyLine.EndPoint.ToString)
    End Sub
End Class