<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

  <StackPanel>

    <TextBox Width="200">
      <TextBox.BitmapEffect>

        <!-- <BitmapEffectGroup> would go here if you wanted to apply more 
             then one effect to the TextBox. However, in this example only  
             one effect is being applied so BitmapEffectGroup does not need  
             to be included. -->

        <!-- The OuterGlow is blue, extends out 30 pixels, has the 
             maximum noise possible, and is 40% Opaque. -->
        <OuterGlowBitmapEffect GlowColor="Blue" GlowSize="30" Noise="1"
         Opacity="0.4" />

      </TextBox.BitmapEffect>
    </TextBox>

  </StackPanel>

</Page>

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">

  <!-- Resources define Styles for the entire page. -->
  <Page.Resources>

    <!-- This style applies to any TextBox on the page. -->
    <Style TargetType="{x:Type TextBox}">
      <Style.Triggers>

        <!-- When the TextBox gains focus such as when the cursor appears
             in the TextBox, apply the OuterGlowBitmapEffect to the TextBox. -->
        <Trigger Property="IsFocused" Value="True">
          <Setter Property = "BitmapEffect" >
            <Setter.Value>

              <!-- The OuterGlow is blue, extends out 30 pixels, has the 
                   maximum noise possible, and is 40% Opaque. -->
              <OuterGlowBitmapEffect GlowColor="Blue" GlowSize="30" Noise="1"
               Opacity="0.4" />
            </Setter.Value>
          </Setter>
        </Trigger>
      </Style.Triggers>
    </Style>
  </Page.Resources>



  <StackPanel>

    <!-- The Style defined above applies to this TextBox which creates
         an outer glow around the it. -->
    <TextBox Name="textBox1"  Width="200" />

  </StackPanel>

</Page>

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
  x:Class="SDKSample.OuterGlowExample" >

  <StackPanel>

    <!-- When this TextBox gains focus, a blue glow surrounds it. -->
    <TextBox Width="200" GotFocus="OnFocusCreateGlow"></TextBox>

  </StackPanel>

</Page>

using System;
using System.Windows;
using System.Windows.Controls;
using System.Windows.Media;
using System.Windows.Input;
using System.Windows.Media.Effects;

namespace SDKSample
{

    public partial class OuterGlowExample : Page
    {

        // Add OuterGlow effect.
        void OnFocusCreateGlow(object sender, RoutedEventArgs args)
        {

            // Get a reference to the TextBox.
            TextBox myTextBox = (TextBox)sender;

            // Initialize a new OuterGlowBitmapEffect that will be applied
            // to the TextBox.
            OuterGlowBitmapEffect myGlowEffect = new OuterGlowBitmapEffect();

            // Set the size of the glow to 30 pixels.
            myGlowEffect.GlowSize = 30;

            // Set the color of the glow to blue.
            Color myGlowColor = new Color();
            myGlowColor.ScA = 1;
            myGlowColor.ScB = 1;
            myGlowColor.ScG = 0;
            myGlowColor.ScR = 0;
            myGlowEffect.GlowColor = myGlowColor;

            // Set the noise of the effect to the maximum possible (range 0-1).
            myGlowEffect.Noise = 1;

            // Set the Opacity of the effect to 40%. Note that the same effect
            // could be done by setting the ScA property of the Color to 0.4.
            myGlowEffect.Opacity = 0.4;

            // Apply the bitmap effect to the TextBox.
            myTextBox.BitmapEffect = myGlowEffect;

        }

    }
}

<Page xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
  xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" >

  <StackPanel>


    <TextBox Width="200">
      <TextBox.BitmapEffect>

        <!-- This BitmapEffect is targeted by the animation. -->
        <OuterGlowBitmapEffect x:Name="myOuterGlowBitmapEffect"  
         GlowColor="Blue" GlowSize="0" />

      </TextBox.BitmapEffect>
      <TextBox.Triggers>
        <EventTrigger RoutedEvent="TextBox.GotFocus">
          <BeginStoryboard>
            <Storyboard>

              <!-- Animate the GlowSize from 0 to 40 over half a second. --> 
              <DoubleAnimation
                Storyboard.TargetName="myOuterGlowBitmapEffect"
                Storyboard.TargetProperty="GlowSize"
                From="0" To="40" Duration="0:0:0.5" />
            </Storyboard>
          </BeginStoryboard>
        </EventTrigger>
      </TextBox.Triggers>
    </TextBox>

  </StackPanel>

</Page>