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TextBoxRenderer Class

Definition

Provides methods used to render a text box control with visual styles. This class cannot be inherited.

public ref class TextBoxRenderer sealed
public ref class TextBoxRenderer abstract sealed
public sealed class TextBoxRenderer
public static class TextBoxRenderer
type TextBoxRenderer = class
Public NotInheritable Class TextBoxRenderer
Public Class TextBoxRenderer
Inheritance
TextBoxRenderer

Examples

The following code example demonstrates how to create a custom control that uses the DrawTextBox method to draw a text box. The control also allows the user to select one of the TextFormatFlags values to apply to the text box text.

#using <System.Drawing.dll>
#using <System.Windows.Forms.dll>
#using <System.dll>

using namespace System;
using namespace System::Text;
using namespace System::Drawing;
using namespace System::Windows::Forms;
using namespace System::Windows::Forms::VisualStyles;

namespace TextBoxRendererSample
{
    public ref class CustomTextBox : public Control
    {
    private:
        TextFormatFlags textFlags;
        ComboBox^ textFormatFlagsComboBox;
        Rectangle textBorder;
        Rectangle textRectangle;
        StringBuilder^ textMeasurements;

    public:
        CustomTextBox():Control()
        {
            textFlags = TextFormatFlags::Default;
            textFormatFlagsComboBox = gcnew ComboBox();

            textMeasurements = gcnew StringBuilder();

            this->Location = Point(10, 10);
            this->Size = System::Drawing::Size(300, 200);
            this->Font = SystemFonts::IconTitleFont;
            this->Text = "This is a long sentence that will exceed " +
                "the text box bounds";

            textBorder.Location = Point(10, 10);
            textBorder.Size = System::Drawing::Size(200, 50);
            textRectangle.Location = Point(textBorder.X + 2,
                textBorder.Y + 2);
            textRectangle.Size =  System::Drawing::Size(textBorder.Size.Width - 4,
                textBorder.Height - 4);

            textFormatFlagsComboBox->Location = Point(10, 100);
            textFormatFlagsComboBox->Size = System::Drawing::Size(150, 20);
            textFormatFlagsComboBox->SelectedIndexChanged +=
                gcnew EventHandler(this, 
                &CustomTextBox::textFormatFlagsComboBox_SelectedIndexChanged);

            // Populate the combo box with the TextFormatFlags value names.
            for each (String^ name in Enum::GetNames(TextFormatFlags::typeid))
            {
                textFormatFlagsComboBox->Items->Add(name);
            }

            textFormatFlagsComboBox->SelectedIndex = 0;
            this->Controls->Add(textFormatFlagsComboBox);
        }

        // Use DrawText with the current TextFormatFlags.

    protected:
        virtual void OnPaint(PaintEventArgs^ e) override
        {
            __super::OnPaint(e);

            if (TextBoxRenderer::IsSupported)
            {
                TextBoxRenderer::DrawTextBox(e->Graphics, textBorder, this->Text,
                    this->Font, textRectangle, textFlags, TextBoxState::Normal);

                this->Parent->Text = "CustomTextBox Enabled";
            }
            else
            {
                this->Parent->Text = "CustomTextBox Disabled";
            }
        }

        // Assign the combo box selection to the display text.
    private:
        void textFormatFlagsComboBox_SelectedIndexChanged(
            Object^ sender, EventArgs^ e)
        {
            this->textFlags = (TextFormatFlags)Enum::Parse(
                TextFormatFlags::typeid,
                (String^)textFormatFlagsComboBox->Items[
                    textFormatFlagsComboBox->SelectedIndex]);

                    Invalidate();
        }
    };

    public ref class Form1 : public Form
    {
    public:
        Form1()
        {
            __super::Form();
            this->Size = System::Drawing::Size(350, 200);
            CustomTextBox^ textBox1 = gcnew CustomTextBox();
            Controls->Add(textBox1);
        }
    };
}

using namespace TextBoxRendererSample;

[STAThread]
int main()
{     
    // The call to EnableVisualStyles below does not affect whether 
    // TextBoxRenderer draws the text box; as long as visual styles 
    // are enabled by the operating system, TextBoxRenderer will 
    // draw the text box.
    Application::EnableVisualStyles();
    Application::Run(gcnew Form1());
}
using System;
using System.Text;
using System.Drawing;
using System.Windows.Forms;
using System.Windows.Forms.VisualStyles;

namespace TextBoxRendererSample
{
    class Form1 : Form
    {
        public Form1()
            : base()
        {
            this.Size = new Size(350, 200);
            CustomTextBox TextBox1 = new CustomTextBox();
            Controls.Add(TextBox1);
        }

        [STAThread]
        static void Main()
        {
            // The call to EnableVisualStyles below does not affect whether 
            // TextBoxRenderer draws the text box; as long as visual styles 
            // are enabled by the operating system, TextBoxRenderer will 
            // draw the text box.
            Application.EnableVisualStyles();
            Application.Run(new Form1());
        }
    }

    public class CustomTextBox : Control
    {
        private TextFormatFlags textFlags = TextFormatFlags.Default;
        ComboBox comboBox1 = new ComboBox();
        Rectangle textBorder = new Rectangle();
        Rectangle textRectangle = new Rectangle();
        StringBuilder textMeasurements = new StringBuilder();

        public CustomTextBox()
            : base()
        {
            this.Location = new Point(10, 10);
            this.Size = new Size(300, 200);
            this.Font = SystemFonts.IconTitleFont;
            this.Text = "This is a long sentence that will exceed " +
                "the text box bounds";

            textBorder.Location = new Point(10, 10);
            textBorder.Size = new Size(200, 50);
            textRectangle.Location = new Point(textBorder.X + 2,
                textBorder.Y + 2);
            textRectangle.Size = new Size(textBorder.Size.Width - 4,
                textBorder.Height - 4);

            comboBox1.Location = new Point(10, 100);
            comboBox1.Size = new Size(150, 20);
            comboBox1.SelectedIndexChanged +=
                new EventHandler(comboBox1_SelectedIndexChanged);

            // Populate the combo box with the TextFormatFlags value names.
            foreach (string name in Enum.GetNames(typeof(TextFormatFlags)))
            {
                comboBox1.Items.Add(name);
            }

            comboBox1.SelectedIndex = 0;
            this.Controls.Add(comboBox1);
        }

        // Use DrawText with the current TextFormatFlags.
        protected override void OnPaint(PaintEventArgs e)
        {
            base.OnPaint(e);

            if (TextBoxRenderer.IsSupported)
            {
                TextBoxRenderer.DrawTextBox(e.Graphics, textBorder, this.Text,
                    this.Font, textRectangle, textFlags, TextBoxState.Normal);

                this.Parent.Text = "CustomTextBox Enabled";
            }
            else
            {
                this.Parent.Text = "CustomTextBox Disabled";
            }
        }

        // Assign the combo box selection to the display text.
        void comboBox1_SelectedIndexChanged(object sender, EventArgs e)
        {
            this.textFlags = (TextFormatFlags)Enum.Parse(
                typeof(TextFormatFlags),
                (string)comboBox1.Items[comboBox1.SelectedIndex]);
            Invalidate();
        }
    }
}
Imports System.Text
Imports System.Drawing
Imports System.Windows.Forms
Imports System.Windows.Forms.VisualStyles

Namespace TextBoxRendererSample

    Class Form1
        Inherits Form

        Public Sub New()
            Me.Size = New Size(350, 200)
            Dim TextBox1 As New CustomTextBox()
            Controls.Add(TextBox1)
        End Sub

        <STAThread()> _
        Shared Sub Main()
            ' The call to EnableVisualStyles below does not affect whether 
            ' TextBoxRenderer draws the text box; as long as visual styles 
            ' are enabled by the operating system, TextBoxRenderer will 
            ' draw the text box.
            Application.EnableVisualStyles()
            Application.Run(New Form1())
        End Sub
    End Class

    Public Class CustomTextBox
        Inherits Control

        Private textFlags As TextFormatFlags = TextFormatFlags.Default
        Private WithEvents comboBox1 As New ComboBox()
        Private textBorder As New Rectangle()
        Private textRectangle As New Rectangle()
        Private textMeasurements As New StringBuilder()

        Public Sub New()

            With Me
                .Location = New Point(10, 10)
                .Size = New Size(300, 200)
                .Font = SystemFonts.IconTitleFont
                .Text = "This is a long sentence that will exceed " + _
                    "the text box bounds"
            End With

            textBorder.Location = New Point(10, 10)
            textBorder.Size = New Size(200, 50)
            textRectangle.Location = New Point(textBorder.X + 2, _
                textBorder.Y + 2)
            textRectangle.Size = New Size(textBorder.Size.Width - 4, _
                textBorder.Height - 4)

            comboBox1.Location = New Point(10, 100)
            comboBox1.Size = New Size(150, 20)

            ' Populate the combo box with the TextFormatFlags value names.
            Dim name As String
            For Each name In [Enum].GetNames(GetType(TextFormatFlags))
                comboBox1.Items.Add(name)
            Next name

            comboBox1.SelectedIndex = 0
            Me.Controls.Add(comboBox1)
        End Sub

        ' Use DrawText with the current TextFormatFlags.
        Protected Overrides Sub OnPaint(ByVal e As PaintEventArgs)
            MyBase.OnPaint(e)

            If TextBoxRenderer.IsSupported Then
                TextBoxRenderer.DrawTextBox(e.Graphics, textBorder, Me.Text, _
                    Me.Font, textRectangle, textFlags, TextBoxState.Normal)
                Me.Parent.Text = "CustomTextBox Enabled"
            Else
                Me.Parent.Text = "CustomTextBox Disabled"
            End If
        End Sub

        ' Assign the combo box selection to the display text.
        Private Sub comboBox1_SelectedIndexChanged(ByVal sender As Object, _
            ByVal e As EventArgs) Handles comboBox1.SelectedIndexChanged

            Me.textFlags = CType([Enum].Parse(GetType(TextFormatFlags), _
                CStr(comboBox1.Items(comboBox1.SelectedIndex))), _
                TextFormatFlags)
            Invalidate()
        End Sub

    End Class
End Namespace

Remarks

The TextBoxRenderer class provides a set of static methods that can be used to render a text box control with the current visual style of the operating system. Rendering a control refers to drawing the user interface of a control. This is useful if you are drawing a custom control that should have the appearance of the current visual style. To draw a text box, use one of the DrawTextBox methods. These methods provide a variety of options, such as applying text formatting or specifying text bounds.

If visual styles are enabled in the operating system and visual styles are applied to the client area of application windows, DrawTextBox will draw the text box with the current visual style. Otherwise, DrawTextBox will throw an InvalidOperationException. To determine whether the members of this class can be used, you can check the value of the IsSupported property.

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

Properties

IsSupported

Gets a value indicating whether the TextBoxRenderer class can be used to draw a text box with visual styles.

Methods

DrawTextBox(Graphics, Rectangle, String, Font, Rectangle, TextBoxState)

Draws a text box control in the specified state and bounds, and with the specified text and text bounds.

DrawTextBox(Graphics, Rectangle, String, Font, Rectangle, TextFormatFlags, TextBoxState)

Draws a text box control in the specified state and bounds, and with the specified text, text bounds, and text formatting.

DrawTextBox(Graphics, Rectangle, String, Font, TextBoxState)

Draws a text box control in the specified state and bounds, and with the specified text.

DrawTextBox(Graphics, Rectangle, String, Font, TextFormatFlags, TextBoxState)

Draws a text box control in the specified state and bounds, and with the specified text and text formatting.

DrawTextBox(Graphics, Rectangle, TextBoxState)

Draws a text box control in the specified state and bounds.

Applies to

See also