.NET 重繪TabControl

　　　　在www.codeproject.com 看到一個關於重繪tabControl的例了，覺得挺有意思的。照着修改一下,有一些東西自己並沒有去改，使得代碼很短，同時也有一些功能並沒實現的。具休可到http://www.codeproject.com/KB/tabs/flattabcontrol.aspx。

我實現的效果如圖：

代碼實現

主要是對TabControl實現的重繪,可以通過繼承TabControl來重繪。

基本上沒什麼難度，有興趣可以試着寫一下。

vb.net 代碼如下：

Imports System.Drawing

Imports System.Drawing.Drawing2D

Imports System.Collections

Imports System.ComponentModel

Imports System.Collections.Generic

Public Class FlatControl



    Sub New()



        ' 此調用是 Windows 窗體設計器所必需的。

        InitializeComponent()



        ' 在 InitializeComponent() 調用之後添加任何初始化。

        SetStyle(ControlStyles.AllPaintingInWmPaint, True)

        SetStyle(ControlStyles.OptimizedDoubleBuffer, True)

        SetStyle(ControlStyles.StandardDoubleClick, True)

        SetStyle(ControlStyles.ResizeRedraw, True)

        SetStyle(ControlStyles.UserPaint, True)

    End Sub



    Protected Overrides Sub OnPaint(ByVal e As System.Windows.Forms.PaintEventArgs)

        MyBase.OnPaint(e)

        DrawTagControl(e.Graphics)

    End Sub

    Dim _backColor As Color = SystemColors.Control

    Public Property backColors() As Color

        Get

            Return _backColor

        End Get

        Set(ByVal value As Color)

            _backColor = value

        End Set

    End Property



    Dim _borderWidth As Integer = SystemInformation.Border3DSize.Width

    Public Property borderWidth() As Integer

        Get

            Return _borderWidth

        End Get

        Set(ByVal value As Integer)

            _borderWidth = value

        End Set

    End Property



    Dim _borderColor As Color = SystemColors.ControlDark





    Public Property borderColor() As Color

        Get

            Return _borderColor

        End Get

        Set(ByVal value As Color)

            _borderColor = value

        End Set

    End Property

    Sub DrawTagControl(ByVal g As Graphics)

        If Me.Visible = False Then

            Exit Sub

        End If



        Dim BackTabArea As Rectangle = Me.ClientRectangle

        Dim UserArea As Rectangle = Me.DisplayRectangle





        'draw AllArea

        Dim BackBrush As New SolidBrush(backColors)

        g.FillRectangle(BackBrush, BackTabArea)

        BackBrush.Dispose()





        'draw border 

        Dim BrPen As New Pen(borderColor, borderWidth)

        UserArea.Inflate(borderWidth, borderWidth)

        g.DrawRectangle(BrPen, UserArea)

        BrPen.Dispose()



        If Me.TabCount > 0 Then



            For i As Integer = 0 To Me.TabCount - 1

                DrawTabs(g, TabPages(i), i)

            Next



        End If

        If Me.SelectedTab IsNot Nothing Then

            Dim tabPage As TabPage = Me.SelectedTab

            Dim color As Color = tabPage.BackColor

            Dim bpen As New Pen(color)

            UserArea.Offset(1, 1)

            UserArea.Width -= 2

            UserArea.Height -= 2

            g.DrawRectangle(bpen, UserArea)

            UserArea.Width -= 1

            UserArea.Height -= 1

            g.DrawRectangle(bpen, UserArea)

            bpen.Dispose()

        End If







    End Sub





    Sub DrawTabs(ByVal g As Graphics, ByVal tabpage As TabPage, ByVal Tindex As Integer)



        Dim TabArea As Rectangle = Me.GetTabRect(Tindex)

        Dim TabTextArea As RectangleF = Me.GetTabRect(Tindex)



        Dim point0 As Point

        Dim point1 As Point

        Dim point2 As Point

        Dim point3 As Point

        Dim point4 As Point

        Dim point5 As Point

        Dim point6 As Point





        '只寫top與下兩個方向的

        If Me.Alignment = TabAlignment.Top Then

            point0 = New Point(TabArea.Left + borderWidth, TabArea.Bottom + 2)

            point1 = New Point(TabArea.Left + borderWidth, TabArea.Top + 3)

            point2 = New Point(TabArea.Left + borderWidth + 3, TabArea.Top)

            point3 = New Point(TabArea.Right - 3, TabArea.Top)

            point4 = New Point(TabArea.Right, TabArea.Top + 3)

            point5 = New Point(TabArea.Right, TabArea.Bottom + 2)

            point6 = point0

        ElseIf Me.Alignment = TabAlignment.Bottom Then

            point0 = New Point(TabArea.Left, TabArea.Top + 2)

            point1 = New Point(TabArea.Left, TabArea.Bottom - 3)

            point2 = New Point(TabArea.Left + 3, TabArea.Bottom)

            point3 = New Point(TabArea.Right - 3, TabArea.Bottom)

            point4 = New Point(TabArea.Right, TabArea.Bottom - 3)

            point5 = New Point(TabArea.Right, TabArea.Top + 2)

            point6 = point0



        End If



        Dim pt() As Point = New Point() {point0, point1, point2, point3, point4, point5, point6}

        '添充

        Dim bBrush As New SolidBrush(tabpage.BackColor)

        g.FillPolygon(bBrush, pt)

        bBrush.Dispose()



        Dim pt1() As Point = New Point() {point0, point1, point2, point3, point4, point5}

        '畫邊

        Dim bpen As New Pen(borderColor, borderWidth)

        g.DrawPolygon(bpen, pt1)

        bpen.Dispose()





        'draw Image 

        If tabpage.ImageIndex >= 0 Then

            Dim LeftSpace As Integer = 8

            Dim Topspace As Single

            Dim img As Image = ImageList.Images(tabpage.ImageIndex)

            Topspace = (TabTextArea.Height - img.Height) / 2 + 1

            g.DrawImage(img, New PointF(LeftSpace + TabTextArea.X, Topspace))

            TabTextArea.Width = TabTextArea.Width - LeftSpace + img.Width

        End If



        'drawText 

        Dim stringFormat As New StringFormat

        stringFormat.Alignment = StringAlignment.Center

        stringFormat.LineAlignment = StringAlignment.Center

        g.DrawString(TabPages(Tindex).Text, Me.Font, Brushes.Black, TabTextArea, stringFormat)



    End Sub



    Private Sub FlatControl_SelectedIndexChanged(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles MyBase.SelectedIndexChanged

        Me.Invalidate()

    End Sub



End Class