在前面的文章中，提到过在vb.net中实现picturebox中图片拖动，以及控件数组方面的东西。
因为项目需要，我要实现的是，图片上有各个站点的名称，我要实现点击相应的名称，进入站点，查看相应的信息。我采取的是在图片上放一系列的label，然后点击label，进入相应的站点，这样就遇到了一个问题，要实现在拖动图片的同时，所有的label也同步拖动。
下面的代码实现了这个功能：
Imports System.Drawing
Namespace WinForm.Main
Public Class MainWindow
Inherits System.Windows.Forms.Form
---- " Windows 窗体设计器生成的代码 "---
Public Sub New()
MyBase.New()
'该调用是 Windows 窗体设计器所必需的。
InitializeComponent()
'在 InitializeComponent() 调用之后添加任何初始化
Me.WindowState = Windows.Forms.FormWindowState.Maximized
loadTree()
Me.L_USER_CONTENT.Text = myForm.LogInUser.get_UserName
'得到picturebox的初始位置坐标
Me.m_Leftx = Me.PictureBox1.Location.X
Me.m_Lefty = Me.PictureBox1.Location.Y
'得到图片的缩放率
Me.m_StrecthX = Me.PictureBox1.Image.Size.Width / Me.PictureBox1.Size.Width
Me.m_StrecthY = Me.PictureBox1.Image.Size.Height / Me.PictureBox1.Size.Height
'添加label双击的绑定
BindArray()
End Sub
------------- Windows 窗体设计器生成的代码----------------------
'处理图片拖动
Private m_Leftx As Integer = 152
Private m_Lefty As Integer = 0
Dim m_MousePosX As Integer
Dim m_MousePosY As Integer
Dim m_DriftX As Integer
Dim m_DriftY As Integer
'缩放率
Dim m_StrecthX As Double
Dim m_StrecthY As Double
'label起始相对于picturebox的位置
Dim m_L_GW_RY_X As Integer
Dim m_L_GW_RY_Y As Integer
Dim m_L_STATION_ZF_X As Integer
Dim m_L_STATION_ZF_Y As Integer
'是否第一次缩放
Dim m_L_FIRST As Boolean = True
'处理label
Dim Labels As New Common.LabelArray(Me)
'当鼠标按下时，将鼠标变成手形，并且记录下当前鼠标的位置
Private Sub PictureBox1_MouseDown(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseDown
Me.Cursor = System.Windows.Forms.Cursors.Hand
m_MousePosX = e.X
m_MousePosY = e.Y
GetLabelPositon()
End Sub
'根据偏移量计算出的图片位置，重画图片
Private Sub picturemove(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs)
Dim myBit As New System.Drawing.Bitmap(PictureBox1.Image)
Dim myPicGrh As System.Drawing.Graphics = Me.PictureBox1.CreateGraphics
myPicGrh.Clear(Me.PictureBox1.BackColor)
myPicGrh.DrawImageUnscaled(myBit, m_Leftx - 152, m_Lefty)
StretchLabel()
myBit.Dispose()
myPicGrh.Dispose()
End Sub
'处理鼠标按键抬起的事件，根据鼠标按下时保存的鼠标位置，和当前鼠标的位置，计算鼠标移动偏移量，借此调用移动图片的函数，移动图片
Private Sub PictureBox1_MouseUp(ByVal sender As Object, ByVal e As System.Windows.Forms.MouseEventArgs) Handles PictureBox1.MouseUp
m_DriftX = m_MousePosX - e.X
m_DriftY = m_MousePosY - e.Y
m_Leftx = m_Leftx - m_DriftX
m_Lefty = m_Lefty - m_DriftY
picturemove(sender, e)
Me.Cursor = System.Windows.Forms.Cursors.Arrow
End Sub
'将管网图上的站点的label用一个事件来处理，处理之前需要绑定
Public Sub BindArray()
Labels.AddItem(Me.L_GW_RY)
Labels.AddItem(Me.L_STATION_ZF)
End Sub
'得到label的起始相对于picture的位置
Public Sub GetLabelPositon()
m_L_GW_RY_X = (Me.L_GW_RY.Location.X - Me.PictureBox1.Location.X) * Me.m_StrecthX + Me.PictureBox1.Location.X
m_L_GW_RY_Y = Me.L_GW_RY.Location.Y * Me.m_StrecthY
m_L_STATION_ZF_X = (Me.L_STATION_ZF.Location.X - Me.PictureBox1.Location.X) * Me.m_StrecthX + Me.PictureBox1.Location.X
m_L_STATION_ZF_Y = Me.L_STATION_ZF.Location.Y * Me.m_StrecthY
End Sub
'根据picture的位置重绘label
Public Sub StretchLabel()
If m_L_FIRST = True Then
Me.L_GW_RY.Font = New System.Drawing.Font("宋体", 9.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
L_GW_RY.SetBounds(Me.m_L_GW_RY_X - m_DriftX, Me.m_L_GW_RY_Y - m_DriftY, L_GW_RY.Width * Me.m_StrecthX, L_GW_RY.Height * Me.m_StrecthY)
Me.L_STATION_ZF.Font = New System.Drawing.Font("宋体", 9.0!, System.Drawing.FontStyle.Regular, System.Drawing.GraphicsUnit.Point, CType(134, Byte))
L_STATION_ZF.SetBounds(Me.m_L_STATION_ZF_X - m_DriftX, Me.m_L_STATION_ZF_Y - m_DriftY, L_STATION_ZF.Width * Me.m_StrecthX, L_STATION_ZF.Height * Me.m_StrecthY)
Else
If ((L_GW_RY.Location.X - m_DriftX) < Me.PictureBox1.Location.X) Or ((L_GW_RY.Location.X - m_DriftX + L_GW_RY.Size.Width) > (Me.PictureBox1.Size.Width)) Then
L_GW_RY.Visible = False
Else
L_GW_RY.Visible = True
End If
If (L_STATION_ZF.Location.X - m_DriftX) < Me.PictureBox1.Location.X Or (L_STATION_ZF.Location.X - m_DriftX + L_STATION_ZF.Size.Width) > (Me.PictureBox1.Size.Width) Then
L_STATION_ZF.Visible = False
Else
L_STATION_ZF.Visible = True
End If
L_GW_RY.SetBounds(L_GW_RY.Location.X - m_DriftX, L_GW_RY.Location.Y - m_DriftY, L_GW_RY.Width, L_GW_RY.Height)
L_STATION_ZF.SetBounds(L_STATION_ZF.Location.X - m_DriftX, L_STATION_ZF.Location.Y - m_DriftY, L_STATION_ZF.Width, L_STATION_ZF.Height)
End If
m_L_FIRST = False
End Sub
End Class
End Namespace
