WPF TextBox show Caret on MouseOver

Question

I am looking for a way to show the Caret in a TextBox when IsMouseOver="True" . The solution using FocusManager.IsFocusScope="True" as mentioned here does not seem to work.

Is there a way to show the Caret without having to click inside the TextBox ?

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MWE:

<Window x:Class="WpfApp11.MainWindow"
        xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
        xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml">
    <Window.Resources>
        <Style BasedOn="{StaticResource {x:Type TextBox}}" TargetType="{x:Type TextBox}">
            <Style.Triggers>
                <Trigger Property="IsMouseOver" Value="True">
                    <Setter Property="FocusManager.IsFocusScope" Value="True" />
                </Trigger>
            </Style.Triggers>
        </Style>
    </Window.Resources>
    <Grid>
        <TextBox Width="300" Height="22" Text="Hello World" />
    </Grid>
</Window>

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A TextBox displaying the Caret after clicking on it. I want the Caret to show already on mouse over.

Answer 1

If you want to set focus, then you need to use FocusedElement ( credits ):

<Style BasedOn="{StaticResource {x:Type TextBox}}"
       TargetType="{x:Type TextBox}">
    <Style.Triggers>
        <Trigger Property="IsMouseOver"
                 Value="True">
            <Setter Property="FocusManager.FocusedElement"
                    Value="{Binding RelativeSource={RelativeSource Self}}" />
        </Trigger>
    </Style.Triggers>
</Style>

If you want caret to be initially at the end then consider to initialize all textboxes like this ( credits ):

<TextBox CaretIndex="{x:Static system:Int32.MaxValue}" ... />

where system is defined like this:

<Window xmlns:system="clr-namespace:System;assembly=mscorlib" ... />