C# Winforms 面板与 TabControl 具有相同的样式（阴影）？

Question

我希望面板有某种像 TabControl 那样的阴影，这可能吗？

Answer 1

BorderStyle = Fix3D

看看本例中的阴影：

http://www.onteorasoftware.com /downloads/panelwithshadow.zip

最后，自定义面板可能类似于（在 VB 中）：

Imports System.Drawing.Drawing2D

Public Class ShadowPanel
  Inherits Panel

  Declare Function GetWindowDC Lib "user32" Alias "GetWindowDC" (ByVal hwnd As IntPtr) _
              As IntPtr
  Declare Function ReleaseDC Lib "user32" Alias "ReleaseDC" (ByVal hwnd As IntPtr, _
      ByVal hdc As IntPtr) As Integer

  Public Sub New()
    Me.BorderStyle = BorderStyle.Fixed3D
  End Sub

  Protected Overrides Sub WndProc(ByRef m As System.Windows.Forms.Message)
    Const WM_NCPAINT As Integer = &H85

    If m.Msg = WM_NCPAINT Then
      Dim hdc As IntPtr = GetWindowDC(m.HWnd)
      Dim g As Graphics = Graphics.FromHdc(hdc)
      Dim rDraw As Rectangle = New Rectangle(0, 0, Me.Width - 1, Me.Height - 1)

      Dim pBottom As Pen = New Pen(Color.Gray, 3)
      Dim pTop As Pen = New Pen(Color.White, 3)

      g.DrawRectangle(pBottom, rDraw)

      Dim pts(2) As Point

      pts(0) = New Point(0, Me.Height - 1)
      pts(1) = New Point(0, 0)
      pts(2) = New Point(Me.Width - 1, 0)

      g.DrawLines(pTop, pts)
      ReleaseDC(Me.Handle, hdc)
    Else
      MyBase.WndProc(m)
    End If
  End Sub

  Private Sub ParentPaint(ByVal sender As Object, ByVal e As System.Windows.Forms.PaintEventArgs) Handles MyBase.Paint
    Dim g As Graphics = Me.Parent.CreateGraphics

    'this matrix zooms the text out to 1/4 size and offsets it by a little right and down
    Dim mx As New Matrix(1.0F, 0, 0, 1.0F, 4, 4)
    Dim rdraw As New Rectangle(Me.Left, Me.Top, Me.Width, Me.Height)

    g.Transform = mx

    g.FillRectangle(New SolidBrush(Color.FromArgb(128, Color.Black)), rdraw)
    g.Dispose()
  End Sub
End Class

Answer 2

是的，在面板的绘制事件中，使用如下内容：

void Paint(object sender, PaintEventArgs e) {
    TabRenderer.DrawTabPage(e.Graphics, e.Bounds);
}