尝试将视图置于ScrollableControl内部元素中心时遇到一些麻烦。
我在ScrollableControl中控制控件没有问题，但每当我尝试设置AutoScrollPosition时，滚动容器内的元素会停靠在ScrollableControl最里面容器的右下角。
这是我正在使用的代码（我非常确定数学是正确的）：
MyBase.AutoScrollPosition = New System.Drawing.Point(Canvas1.Left - ((MyBase.Width - Canvas1.Size.Width) / 2), Canvas1.Top - ((MyBase.Height - Canvas1.Size.Height) / 2))
项目的类型实际上是UserControl，而不是Class，因此这不是“继承的”ScrollableControl本身。它是UserControl类型。
我发现最令人头晕目眩的是，似乎没有ScrollToX，只有ScrollControlIntoView等等，这些都不符合我的意愿。
基本上，最终结果是，Viewable区域的中心必须是Scrollable虚拟区域内包含的Control的中心。我将控件置于中心位置，所以这实际上只是将其滚动到视图中，因此内部控件死点的X，Y位于可视区域的死点。
整个班级的当前代码
Imports System.ComponentModel
Public Class Board
Private _init As Boolean = False
Private _keys As KeyEventArgs = Nothing
''' <summary>
''' </summary>
''' <filterpriority>3</filterpriority>
''' <remarks></remarks>
<Browsable(False), EditorBrowsable(False)> _
Shadows Property BackgroundImage As Image
Get
Return MyBase.BackgroundImage
End Get
Set(value As Image)
MyBase.BackgroundImage = value
End Set
End Property
<Browsable(False), EditorBrowsable(False)> _
Shadows Property AutoScroll As Boolean
Get
Return MyBase.AutoScroll
End Get
Set(value As Boolean)
MyBase.AutoScroll = value
End Set
End Property
<Browsable(False), EditorBrowsable(False)> _
Shadows Property AutoScrollMinSize As System.Drawing.Size
Get
Return MyBase.AutoScrollMinSize
End Get
Set(value As System.Drawing.Size)
MyBase.AutoScrollMinSize = value
End Set
End Property
Public Property Checkerboard As Boolean
Get
Return Canvas1.CheckeredBackground
End Get
Set(value As Boolean)
Canvas1.CheckeredBackground = value
End Set
End Property
Shadows Property BorderStyle As Windows.Forms.BorderStyle
Get
Return Canvas1.BorderStyle
End Get
Set(value As Windows.Forms.BorderStyle)
Canvas1.BorderStyle = value
End Set
End Property
Private Sub Canvas1_MouseEnter(sender As Object, e As EventArgs) Handles Canvas1.MouseEnter
Me.Focus()
End Sub
Public Sub Add(ByVal Image As System.Drawing.Image)
Dim l As New Layer("Layer " & Canvas1.Layers.Count + 1)
l.Graphics.Add(New Graphic(Image, New Point(10, 10)))
Canvas1.Layers.Add(l)
End Sub
Public Property CanvasSize() As System.Drawing.Size
Get
Return Canvas1.Size
End Get
Set(value As System.Drawing.Size)
Canvas1.Size = value
Me.CenterCanvas()
End Set
End Property
Public Property BoardSize() As System.Drawing.Size
Get
Return Me.AutoScrollMinSize
End Get
Set(value As System.Drawing.Size)
Me.AutoScrollMinSize = value
Me.CenterCanvas()
End Set
End Property
Public Function Remove(ByVal Index As Integer) As Boolean
Try
Canvas1.Layers.RemoveAt(Index)
Return True
Catch ex As Exception
Return False
End Try
End Function
Public Sub RefreshCanvas()
Canvas1.Invalidate()
End Sub
Public Sub CenterCanvas()
Canvas1.Location = New System.Drawing.Point((MyBase.DisplayRectangle.Width - Canvas1.Size.Width) / 2, (MyBase.DisplayRectangle.Height - Canvas1.Size.Height) / 2)
'Debug.Print(Canvas1.Top & ", " & Canvas1.Left)
' Dim y As Integer = (Me.Height - Canvas1.Height) / 2
' Dim x As Integer = (Me.Width - Canvas1.Width) / 2
' x = Canvas1.Left - x
' y = Canvas1.Top - y
' Me.AutoScrollPosition = New System.Drawing.Point(x, y)
End Sub
Public Sub New()
' This call is required by the designer.
InitializeComponent()
_init = True
' Add any initialization after the InitializeComponent() call.
Me.CenterCanvas()
End Sub
Private Sub Board_KeyDown(sender As Object, e As KeyEventArgs) Handles Me.KeyDown
_keys = e
End Sub
Private Sub Board_KeyUp(sender As Object, e As KeyEventArgs) Handles Me.KeyUp
_keys = Nothing
End Sub
Private Sub Board_MouseWheel(sender As Object, e As MouseEventArgs) Handles Me.MouseWheel
Dim l As Layer
l = Canvas1.SelectedLayer
If IsNothing(l) = False Then
Debug.Print("Wheels")
End If
Dim MW As HandledMouseEventArgs = e
MW.Handled = False
End Sub
Private Sub Board_Resize(sender As Object, e As EventArgs) Handles Me.Resize
' If _init Then
' Dim x As Integer = Canvas1.Left - ((MyBase.Width - Canvas1.Size.Width) / 2)
'Dim y As Integer = Canvas1.Top - ((MyBase.Height - Canvas1.Size.Height) / 2)
' MyBase.AutoScrollPosition = New System.Drawing.Point(Canvas1.Left - ((MyBase.Width - Canvas1.Size.Width) / 2), Canvas1.Top - ((MyBase.Height - Canvas1.Size.Height) / 2))
'End If
MyBase.AutoScrollPosition = New System.Drawing.Point( _
Canvas1.Left - MyBase.AutoScrollPosition.X - ((MyBase.ClientSize.Width - Canvas1.Size.Width) \ 2), _
Canvas1.Top - MyBase.AutoScrollPosition.Y - ((MyBase.ClientSize.Height - Canvas1.Size.Height) \ 2))
End Sub
Private Sub Board_SizeChanged(sender As Object, e As EventArgs) Handles Me.SizeChanged
End Sub
End Class
<Global.Microsoft.VisualBasic.CompilerServices.DesignerGenerated()> _
Partial Class Board
Inherits System.Windows.Forms.UserControl
'UserControl1 overrides dispose to clean up the component list.
<System.Diagnostics.DebuggerNonUserCode()> _
Protected Overrides Sub Dispose(ByVal disposing As Boolean)
Try
If disposing AndAlso components IsNot Nothing Then
components.Dispose()
End If
Finally
MyBase.Dispose(disposing)
End Try
End Sub
'Required by the Windows Form Designer
Private components As System.ComponentModel.IContainer
'NOTE: The following procedure is required by the Windows Form Designer
'It can be modified using the Windows Form Designer.
'Do not modify it using the code editor.
<System.Diagnostics.DebuggerStepThrough()> _
Private Sub InitializeComponent()
Me.Canvas1 = New Artisto.Canvas()
CType(Me.Canvas1, System.ComponentModel.ISupportInitialize).BeginInit()
Me.SuspendLayout()
'
'Canvas1
'
Me.Canvas1.Anchor = System.Windows.Forms.AnchorStyles.None
Me.Canvas1.CheckeredBackground = True
Me.Canvas1.Location = New System.Drawing.Point(0, 0)
Me.Canvas1.Name = "Canvas1"
Me.Canvas1.SelectedLayer = Nothing
Me.Canvas1.Size = New System.Drawing.Size(619, 317)
Me.Canvas1.TabIndex = 0
Me.Canvas1.TabStop = False
'
'Board
'
Me.AutoScaleMode = System.Windows.Forms.AutoScaleMode.Inherit
Me.AutoScroll = True
Me.AutoScrollMinSize = New System.Drawing.Size(4096, 2160)
Me.AutoSizeMode = System.Windows.Forms.AutoSizeMode.GrowAndShrink
Me.Controls.Add(Me.Canvas1)
Me.DoubleBuffered = True
Me.Name = "Board"
Me.Size = New System.Drawing.Size(1266, 523)
CType(Me.Canvas1, System.ComponentModel.ISupportInitialize).EndInit()
Me.ResumeLayout(False)
End Sub
Friend WithEvents Canvas1 As Artisto.Canvas
End Class