Draw text to the background of a control by accessing the control's DrawingContext. : DrawingGroup « Windows Presentation Foundation « C# / CSharp Tutorial






<Window x:Class="WpfApplication1.Window1"
  xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  Title="Draw Text to a Control's Background"
  Background="FloralWhite"
  Width="800" 
  Loaded="WindowLoaded">

  <StackPanel>
      <Label Name="myLabel" Width="200" Height="36" />
      <TextBox Name="myTextBox" MaxLength="25" >Sample Text</TextBox>
      <Button Name="myButton" Click="OnButtonClick" Width="160" Height="40" />
      <Canvas Name="myCanvas" Width ="760" Height="300"/>
  </StackPanel>
</Window>

//File:Window.xaml.cs

using System;
using System.Globalization;
using System.Windows;
using System.Windows.Media;

namespace WpfApplication1
{
    public partial class Window1 : Window
    {
        public Window1() : base()
        {
            InitializeComponent();
        }

        private void WindowLoaded(object sender, EventArgs e) 
        {
            myLabel.Background = new DrawingBrush(DrawMyText("My Custom Label"));
            myButton.Background = new DrawingBrush(DrawMyText("Display Text"));
        }
        private Drawing DrawMyText(string textString)
        {
            DrawingGroup drawingGroup = new DrawingGroup();
            using (DrawingContext drawingContext = drawingGroup.Open())
            {
                FormattedText formattedText = new FormattedText(
                    textString,
                    CultureInfo.GetCultureInfo("en-us"),
                    FlowDirection.LeftToRight,
                    new Typeface("Comic Sans MS Bold"),
                    48,
                    Brushes.Black 
                    );
                Geometry textGeometry = formattedText.BuildGeometry(new Point(20, 0));
                drawingContext.DrawRoundedRectangle(Brushes.PapayaWhip, null, new Rect(new Size(formattedText.Width + 50, formattedText.Height + 5)), 5.0, 5.0);
                drawingContext.DrawGeometry(Brushes.Gold, new Pen(Brushes.Maroon, 1.5), textGeometry);
                return drawingGroup;
            }
        }
        public void OnButtonClick(object sender, EventArgs e)
        {
            myCanvas.Background = new DrawingBrush(DrawMyText(myTextBox.Text));
        }
    }
}
WPF Draw Text To The Background Of A Control By Accessing The Controls Drawing Context








24.99.DrawingGroup
24.99.1.DrawingGroup and GeometryGroupDrawingGroup and GeometryGroup
24.99.2.Draw text to the background of a control by accessing the control's DrawingContext.Draw text to the background of a control by accessing the control's DrawingContext.