介绍：
我正在使用最初由@Hans Passant 在这里编写的自定义消息框类：Winforms-如何使 MessageBox 以 MainForm 为中心显示？
（我正在使用的修改版本在这个问题的底部）
自定义消息框可以接收自定义文本字体来显示它。
这是一个使用示例：
Using New CenteredMessageBox(Me, _
New Font(New FontFamily("Lucida Console"), 16, FontStyle.Bold))
MessageBox.Show("Test Text", "Test Title", MessageBoxButtons.YesNo, MessageBoxIcon.Question)
End Using
问题：
窗口的所有内容都需要手动调整大小/位置，如果没有，文本将被裁剪显示如下：
这就是结果如果我使用更大的字体（我已经调整了文本控件的大小）：
所以我需要计算哪个位置和大小将使元素真正与字体大小相匹配，以调整窗口大小并定位按钮，这就是我所要求的。我该怎么做？我需要的不仅仅是一个公式，因为我做的数学不太好。
要素：
我想到了这些元素：
- 消息框文本字体大小。
- 包含并显示文本的 Messagebox 静态控件。
- 消息框按钮（可以是 1 个按钮、2 个按钮或 3 个按钮的组合，具有不同的默认位置）
- 包含所有这些元素的消息框窗口窗体。
按钮变量：
- 如果消息框窗口中只有 1 个按钮（例如：'Ok'），它将对齐到中间，但如果它们是 3 个按钮（例如：'AbortRetryIgnore'），那么第一个按钮将对齐到左下角，第二个按钮到中间和最后一个按钮到右上角，我认为没有必要解释这个，因为大家都知道msgbox如何显示他们的按钮。
我不是算术大师，所以如果我错过了一些必要的值，请原谅我，但我认为这些将是代码中必须使用的值/变量：
Dim Text_width As Integer = 0
Dim Text_height As Integer = 0
Dim Text_Container_width As Integer = 0
Dim Text_Container_height As Integer = 0
' Don't calculate the exact size of messagebox window,
' just I think only needs to sum an extra size to a default messagebox rectangle
Dim Messagebox_window_extra_width As Integer = 0
Dim Messageboxwindow_extra_height As Integer = 0
' This represents the first button,
' in a messagebox button combination of 1, 2, or 3 buttons,
' this button could be displayed alligned at bottom-middle (as unique button),
' or could be alligned at bottom-left (as the first of 2 of 3 button combination).
Dim Button_1_Pos_X As Integer = 0
Dim Button_1_Pos_Y As Integer = 0
' This button represents the second button
' in a messagebox button combination of 2 or 3 buttons,
' the buton could exist or could not
' and could be displayed alligned at bottom-middle (in the middle of 3 buttons),
' this button could be displayed alligned at bottom-right (as second and last button).
Dim Button_2_Pos_X As Integer = 0
Dim Button_2_Pos_Y As Integer = 0
' This button represents the third button
' a messagebox button combination of 2 or 3 buttons,
' the buton could exist or could not
' and could be displayed alligned at bottom-right (as third and last button).
Dim Button_3_Pos_X As Integer = 0
Dim Button_3_Pos_Y As Integer = 0
这是我自己可以做的，我一直在测试以这种方式存储消息框按钮元素：
Dim button_Ok As IntPtr = GetDlgItem(hWnd, 1) ' The 'Ok' button.
Dim button_Cancel As IntPtr = GetDlgItem(hWnd, 2) ' the 'Cancel' button.
Dim button_Abort As IntPtr = GetDlgItem(hWnd, 3) ' the 'Abort' button.
Dim button_Retry As IntPtr = GetDlgItem(hWnd, 4) ' the 'Retry' button.
Dim button_Ignore As IntPtr = GetDlgItem(hWnd, 5) ' the 'Ignore' button.
Dim button_Yes As IntPtr = GetDlgItem(hWnd, 6) ' the 'Yes' button.
Dim button_No As IntPtr = GetDlgItem(hWnd, 7) ' the 'NO' button.
（无论消息框按钮组合如何，它们始终具有相同的项目索引）
要调整消息框窗口的大小，我可以使用 MoveWindow API，如下所示：
' This is to resize and positionate the messagebox window
MoveWindow(hWnd, _
frmRect.Left + (frmRect.Width - dlgRect.Right + dlgRect.Left) \ 2, _
frmRect.Top + (frmRect.Height - dlgRect.Bottom + dlgRect.Top) \ 2, _
(dlgRect.Right - dlgRect.Left) + Messagebox_window_extra_width, _
(dlgRect.Bottom - dlgRect.Top) + Messagebox_window_extra_height, True)
并且要调整其余元素（文本容器、按钮）的大小，在调整消息框表单的大小之后，我可以像这样使用 SetWindowPos API：
' Text container:
SetWindowPos(hText, 0, 70, 30, 1920, 1080, 0) ' Values are not perfect calculated but works fine
' Messagebox buttons:
' SetWindowPos(button_Ok, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Cancel, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Abort, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Retry, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Ignore, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Yes, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_No, 0, 0, 0, 0, 0, 0)
消息框类
这里把我之前提到的所有事情都搞砸了：
' [ Centered MessageBox ]
'
' The author of the original code is Hans Passant: https://stackoverflow.com/questions/2576156/winforms-how-can-i-make-messagebox-appear-centered-on-mainform
'
' Examples :
'
' Using New CenteredMessageBox(Me, New Font(New FontFamily("Lucida Console"), Font.SizeInPoints, FontStyle.Bold))
' MessageBox.Show("Test Text", "Test Title", MessageBoxButtons.OK, MessageBoxIcon.Information)
' End Using
#Region " Centered MessageBox Class"
Imports System.Drawing
Imports System.Runtime.InteropServices
Imports System.Text
Imports System.Windows.Forms
Class CenteredMessageBox : Implements IDisposable
Private mTries As Integer = 0
Private mOwner As Form
Private mFont As Font
Dim Text_width As Integer = 0
Dim Text_height As Integer = 0
Dim Text_Container_width As Integer = 0
Dim Text_Container_height As Integer = 0
Dim Messagebox_window_extra_width As Integer = 0
Dim Messagebox_window_extra_height As Integer = 0
Dim Button_1_Pos_X As Integer = 0 ' "OK" Button
Dim Button_1_Pos_Y As Integer = 0 ' "OK" Button
Dim Button_2_Pos_X As Integer = 0 ' This button could not exist
Dim Button_2_Pos_Y As Integer = 0 ' This button could not exist
Dim Button_3_Pos_X As Integer = 0 ' This button could not exist
Dim Button_3_Pos_Y As Integer = 0 ' This button could not exist
' P/Invoke declarations
Private Const WM_SETFONT As Integer = &H30
Private Const WM_GETFONT As Integer = &H31
Private Delegate Function EnumThreadWndProc(hWnd As IntPtr, lp As IntPtr) As Boolean
<DllImport("user32.dll")> _
Private Shared Function EnumThreadWindows(tid As Integer, callback As EnumThreadWndProc, lp As IntPtr) As Boolean
End Function
<DllImport("kernel32.dll")> _
Private Shared Function GetCurrentThreadId() As Integer
End Function
<DllImport("user32.dll")> _
Private Shared Function GetClassName(hWnd As IntPtr, buffer As StringBuilder, buflen As Integer) As Integer
End Function
<DllImport("user32.dll")> _
Private Shared Function GetDlgItem(hWnd As IntPtr, item As Integer) As IntPtr
End Function
<DllImport("user32.dll")> _
Private Shared Function SendMessage(hWnd As IntPtr, msg As Integer, wp As IntPtr, lp As IntPtr) As IntPtr
End Function
<DllImport("user32.dll")> _
Shared Function GetWindowRect(hWnd As IntPtr, ByRef rc As RECT) As Boolean
End Function
<DllImport("user32.dll")> _
Shared Function MoveWindow(hWnd As IntPtr, x As Integer, y As Integer, w As Integer, h As Integer, repaint As Boolean) As Boolean
End Function
Structure RECT
Public Left As Integer
Public Top As Integer
Public Right As Integer
Public Bottom As Integer
End Structure
Friend Declare Function SetWindowPos Lib "user32" (ByVal hwnd As IntPtr, ByVal hWndInsertAfter As IntPtr, ByVal x As Integer, ByVal y As Integer, ByVal cx As Integer, ByVal cy As Integer, ByVal wFlags As UInt32) As Boolean
Public Sub New(owner As Form, Optional Custom_Font As Font = Nothing)
mOwner = owner
mFont = Custom_Font
owner.BeginInvoke(New MethodInvoker(AddressOf findDialog))
End Sub
Private Sub findDialog()
' Enumerate windows to find the message box
If mTries < 0 Then
Return
End If
Dim callback As New EnumThreadWndProc(AddressOf checkWindow)
If EnumThreadWindows(GetCurrentThreadId(), callback, IntPtr.Zero) Then
If System.Threading.Interlocked.Increment(mTries) < 10 Then
mOwner.BeginInvoke(New MethodInvoker(AddressOf findDialog))
End If
End If
End Sub
Private Function checkWindow(hWnd As IntPtr, lp As IntPtr) As Boolean
' Checks if <hWnd> is a dialog
Dim sb As New StringBuilder(260)
GetClassName(hWnd, sb, sb.Capacity)
If sb.ToString() <> "#32770" Then Return True
' Got it, get the STATIC control that displays the text
Dim hText As IntPtr = GetDlgItem(hWnd, &HFFFF)
' Get the messagebox button elements
Dim button_Ok As IntPtr = GetDlgItem(hWnd, 1) ' The 'Ok' button.
Dim button_Cancel As IntPtr = GetDlgItem(hWnd, 2) ' the 'Cancel' button.
Dim button_Abort As IntPtr = GetDlgItem(hWnd, 3) ' the 'Abort' button.
Dim button_Retry As IntPtr = GetDlgItem(hWnd, 4) ' the 'Retry' button.
Dim button_Ignore As IntPtr = GetDlgItem(hWnd, 5) ' the 'Ignore' button.
Dim button_Yes As IntPtr = GetDlgItem(hWnd, 6) ' the 'Yes' button.
Dim button_No As IntPtr = GetDlgItem(hWnd, 7) ' the 'NO' button.
Dim frmRect As New Rectangle(mOwner.Location, mOwner.Size)
Dim dlgRect As RECT
GetWindowRect(hWnd, dlgRect)
If hText <> IntPtr.Zero Then
If mFont Is Nothing Then
' Get the current font
mFont = Font.FromHfont(SendMessage(hText, WM_GETFONT, IntPtr.Zero, IntPtr.Zero))
End If
SendMessage(hText, WM_SETFONT, mFont.ToHfont(), New IntPtr(1))
' Just here is an empty space where I can test some operations:
'
' Messagebox_window_extra_width = (mFont.Height \ mFont.Size) + (dlgRect.Right)
' Messagebox_window_extra_height = mFont.Height +
' This is to resize and positionate the messagebox window:
MoveWindow(hWnd, _
frmRect.Left + (frmRect.Width - dlgRect.Right + dlgRect.Left) \ 2, _
frmRect.Top + (frmRect.Height - dlgRect.Bottom + dlgRect.Top) \ 2, _
(dlgRect.Right - dlgRect.Left) + Messagebox_window_extra_width, _
(dlgRect.Bottom - dlgRect.Top) + Messagebox_window_extra_height, True)
' And this is to resize and positionate the rest elements:
'
' Text container:
SetWindowPos(hText, 0, 70, 30, 1920, 1080, 0)
'
' Messagebox buttons:
' SetWindowPos(button_Ok, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Cancel, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Abort, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Retry, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Ignore, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_Yes, 0, 0, 0, 0, 0, 0)
' SetWindowPos(button_No, 0, 0, 0, 0, 0, 0)
End If
' Done
Return False
End Function
Public Sub Dispose() Implements IDisposable.Dispose
mTries = -1
mOwner = Nothing
If mFont IsNot Nothing Then mFont.Dispose()
End Sub
End Class
#End Region
更新
这就是我尝试使用@Grahamvs 解决方案的原因：
Using New CenteredMessageBox(Me, New Font(New FontFamily("Lucida Console"), Font.SizeInPoints, FontStyle.Bold))
MessageBox.Show("Test Text", "Test Title", MessageBoxButtons.OK, MessageBoxIcon.Information)
End Using