如何让仪表指针绕某点旋转
我想做一个仪表，用panel控件，背景图是仪表盘，然后在上面放了一个picturebox控件，image是指针。
我想让指针绕着靠近末端的一点转动，也就是让picturebox绕着某一点转动。我只要输入0的时候，指针指向仪表盘的0刻度，输入100时指向最大刻度。仪表盘上的0到最大刻度之间大概有150度。
如果有更好的思路做仪表盘的，也请指导一下，谢谢！！！
[解决办法]
http://download.csdn.net/detail/wuyazhe/2090762
按这里的例子，可以自己绘制指针，旋转画布。
[解决办法]
参考一下
[解决办法]
Public Class ybp
Inherits PictureBox
''' <summary>
''' 用这个背景图来放你的仪表盘
''' </summary>
''' <value></value>
''' <returns></returns>
''' <remarks></remarks>
Public Overloads Property BackgroundImage() As Image
Get
Return MyBase.BackgroundImage
End Get
Set(ByVal value As Image)
Me.Width = value.Width
Me.Height = value.Height
Me.Location = New Point(Me.Parent.Width / 2 - Me.Width / 2, Me.Parent.Height / 2 - Me.Height / 2)
MyBase.BackgroundImage = value
End Set
End Property
Dim _Value As Integer = 35
''' <summary>
''' 仪表盘最大量程，即最大数值
''' </summary>
''' <value></value>
''' <returns></returns>
''' <remarks></remarks>
Public Property Value() As Integer
Get
Return _Value
End Get
Set(ByVal value As Integer)
_Value = value
Me.Refresh()
End Set
End Property
Dim ZzColor As Color
Dim ZzWidth As Integer
Dim ZzSlength As Integer
Dim ZzClength As Integer
Dim MaxNumber As Integer = 100
Private Sub ybp_Paint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles Me.Paint
Dim ZzColor As Color = Color.Red
Dim ZzWidth As Integer = 3
Dim ZzSlength As Integer = Math.Min(Width, Height) / 5
Dim ZzClength As Integer = Math.Min(Width, Height) / 2 - 10
e.Graphics.DrawEllipse(New Pen(Color.Red, 1), New Rectangle(Width / 2 - 2, Height / 2 - 2, 5, 5))
e.Graphics.DrawLine(New Pen(ZzColor, ZzWidth), CSng(Width / 2 + ZzClength * Math.Sin(_Value / MaxNumber * 2 * Math.PI)), _
CSng(Height / 2 - ZzClength * Math.Cos(_Value / MaxNumber * 2 * Math.PI)), CSng(Width / 2), CSng(Height / 2))
End Sub
End Class
Public Class Form1
Dim bb As Image
Dim bt As Image
Dim bv As Image
Dim grb As Graphics
Dim grv As Graphics
Dim len As Integer = 200
Dim ft As Integer = 120
Dim ang As Single = 150 / ft
Dim sang As Single = 150
Dim inc As Boolean
Private Sub Form1_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
Me.Height = len + Me.Height - Me.ClientRectangle.Height
Me.Width = len + Me.Width - Me.ClientRectangle.Width
bb = New Bitmap(len, len)
bt = New Bitmap(len \ 2, len \ 2)
bv = New Bitmap(len, len)
Graphics.FromImage(bb).FillPie(Brushes.Black, New Rectangle(Point.Empty, bb.Size), 0, 360)
Graphics.FromImage(bt).DrawLine(Pens.Red, Point.Empty, New PointF(bt.Width / Math.Sqrt(2), bt.Height / Math.Sqrt(2)))
grb = Graphics.FromImage(bv)
grv = Graphics.FromHwnd(Me.Handle)
End Sub
Private Sub Button1_Click(sender As System.Object, e As System.EventArgs) Handles Button1.Click
For i = 0 To ft
Threading.Thread.Sleep(10)
grb.DrawImage(bb, Point.Empty)
grb.TranslateTransform(len \ 2, len \ 2)
grb.RotateTransform(ang * i + sang)
grb.DrawImage(bt, Point.Empty)
grb.RotateTransform(-ang * i - sang)
grb.TranslateTransform(-len \ 2, -len \ 2)
grv.DrawImage(bv, Point.Empty)
Next
End Sub
End Class
