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CheckBoxRenderer Class

Provides methods used to render a check box control with or without visual styles. This class cannot be inherited.

Namespace:  System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

Public NotInheritable Class CheckBoxRenderer
Dim instance As CheckBoxRenderer

The CheckBoxRenderer class provides a set of static methods that can be used to render a check box control. Rendering a control refers to drawing the user interface of a control. To draw a check box, use one of the DrawCheckBox methods. These methods provide a variety of options, such as drawing text or an image with the check box.

If visual styles are enabled in the operating system and visual styles are applied to the current application, DrawCheckBox will draw the check box with the current visual style. Otherwise, DrawCheckBox will draw the check box with the classic Windows style. This is useful if you are drawing a custom control that should automatically match the current visual style setting of the operating system.

This class wraps the functionality of a System.Windows.Forms.VisualStyles.VisualStyleRenderer that is set to one of the elements exposed by the System.Windows.Forms.VisualStyles.VisualStyleElement.Button.CheckBox class. For more information, see Rendering Controls with Visual Styles.

Windows XP Home Edition, Windows XP Professional x64 Edition, Windows Server 2003 Platform Note: Visual styles are supported only on these platforms.

The following code example demonstrates how to write a custom control that uses the DrawCheckBox method to draw a check box that responds to mouse clicks.

Imports System
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.VisualStyles

Namespace CheckBoxRendererSample

    Class Form1
        Inherits Form

        Public Sub New()
            Dim CheckBox1 As New CustomCheckBox()

            If Application.RenderWithVisualStyles Then 
                Me.Text = "Visual Styles Enabled" 
                Me.Text = "Visual Styles Disabled" 
            End If 
        End Sub

        <STAThread()> _
        Shared Sub Main()
            ' If you do not call EnableVisualStyles below, then  
            ' CheckBoxRenderer.DrawCheckBox automatically detects    
            ' this and draws the check box without visual styles.
            Application.Run(New Form1())
        End Sub 
    End Class 

    Public Class CustomCheckBox
        Inherits Control

        Private textRectangleValue As New Rectangle()
        Private clickedLocationValue As New Point()
        Private clicked As Boolean = False 
        Private state As CheckBoxState = CheckBoxState.UncheckedNormal

        Public Sub New()
            With Me
                .Location = New Point(50, 50)
                .Size = New Size(100, 20)
                .Text = "Click here"
                .Font = SystemFonts.IconTitleFont
            End With 
        End Sub 

        ' Calculate the text bounds, exluding the check box. 
        Public ReadOnly Property TextRectangle() As Rectangle
                Using g As Graphics = Me.CreateGraphics()
                    With textRectangleValue
                        .X = Me.ClientRectangle.X + _
                            CheckBoxRenderer.GetGlyphSize(g, _
                        .Y = Me.ClientRectangle.Y
                        .Width = Me.ClientRectangle.Width - _
                            CheckBoxRenderer.GetGlyphSize(g, _
                        .Height = Me.ClientRectangle.Height
                    End With 
                End Using 
                Return textRectangleValue
            End Get 
        End Property 

        ' Draw the check box in the current state. 
        Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
            CheckBoxRenderer.DrawCheckBox(e.Graphics, _
                Me.ClientRectangle.Location, TextRectangle, Me.Text, _
                Me.Font, TextFormatFlags.HorizontalCenter, _
                clicked, state)
        End Sub 

        ' Draw the check box in the checked or unchecked state, alternately. 
        Protected Overrides Sub OnMouseDown(ByVal e As MouseEventArgs)
            If Not clicked Then 
                With Me
                    .clicked = True
                    .Text = "Clicked!"
                    .state = CheckBoxState.CheckedPressed
                End With
                With Me
                    .clicked = False
                    .Text = "Click here"
                    .state = CheckBoxState.UncheckedNormal
                End With
            End If 
        End Sub 

        ' Draw the check box in the hot state.  
        Protected Overrides Sub OnMouseHover(ByVal e As EventArgs)
            If clicked Then
                state = CheckBoxState.CheckedHot
                state = CheckBoxState.UncheckedHot
            End If
        End Sub 

        ' Draw the check box in the hot state.  
        Protected Overrides Sub OnMouseUp(ByVal e As MouseEventArgs)
        End Sub 

        ' Draw the check box in the unpressed state. 
        Protected Overrides Sub OnMouseLeave(ByVal e As EventArgs)
            If clicked Then
                state = CheckBoxState.CheckedNormal
                state = CheckBoxState.UncheckedNormal
            End If
        End Sub 

    End Class 
End Namespace


Any public static (Shared in Visual Basic) members of this type are thread safe. Any instance members are not guaranteed to be thread safe.

Windows 7, Windows Vista, Windows XP SP2, Windows XP Media Center Edition, Windows XP Professional x64 Edition, Windows XP Starter Edition, Windows Server 2008 R2, Windows Server 2008, Windows Server 2003, Windows Server 2000 SP4, Windows Millennium Edition, Windows 98

The .NET Framework and .NET Compact Framework do not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

.NET Framework

Supported in: 3.5, 3.0, 2.0

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