WPF TextBox Border when selected?

Question

I want to make a WPF TextBox have a DarkBlue border and thickness equal to 1. I want to make the WPF have this border ( DarkBlue, thickness set to 1 ) even when the TextBox is selected.

I tried doing this task by the following code. However, it doesn't work at all. Any ideas or hints ? Any help would be greatly appreciated.

  <Style x:Key="ReadOnlyLargeTextBox" TargetType="{x:Type TextBox}" >
        <Setter Property="Height" Value="80"/>
        <Setter Property="MaxHeight" Value="80"/>

        <Setter Property="VerticalScrollBarVisibility" Value="Visible"/>
        <Style.Triggers>
            <Trigger Property="TextBox.IsMouseOver"    Value="True">
                <Setter Property="BorderBrush" Value="DarkBlue"/>
                <Setter Property="BorderThickness" Value="1"/>
            </Trigger>
            <Trigger Property="TextBox.IsMouseOver"    Value="False">
                <Setter Property="BorderBrush" Value="DarkBlue"/>
                <Setter Property="BorderThickness" Value="1"/>
            </Trigger>
        </Style.Triggers>


    </Style>

P.S Note that the text box does not have an IsSelected property.

Answer 1

just see is this you want...

<Style x:Key="TextBoxStyle1" BasedOn="{x:Null}" TargetType="{x:Type TextBox}">
        <Setter Property="BorderThickness" Value="1"/>
        <Setter Property="Padding" Value="1"/>
        <Setter Property="AllowDrop" Value="true"/>
        <Setter Property="FocusVisualStyle" Value="{x:Null}"/>
        <Setter Property="Template">
            <Setter.Value>
                <ControlTemplate TargetType="{x:Type TextBox}">
                <Border x:Name="bg" BorderBrush="#FF825E5E" BorderThickness="1">
                        <ScrollViewer x:Name="PART_ContentHost" SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
                        </Border>
                    <ControlTemplate.Triggers>

                        <Trigger Property="IsMouseOver" Value="True">
                            <Setter Property="BorderBrush" TargetName="bg" Value="DarkBlue"/>
                            <Setter Property="BorderThickness" TargetName="bg" Value="2"/>
                        </Trigger>
                        <Trigger Property="IsFocused" Value="True">
                            <Setter Property="BorderBrush" TargetName="bg" Value="DarkBlue"/>
                            <Setter Property="BorderThickness" TargetName="bg" Value="2"/>
                        </Trigger>

                    </ControlTemplate.Triggers>
                </ControlTemplate>
            </Setter.Value>
        </Setter>
    </Style>