How do I enable drag/drop of text from textblock to textbox in windows store apps

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C#

Windows

XAML

Windows-Store

I have the following xaml

<Grid AllowDrop="True">
        <TextBlock x:Name="readText" VerticalAlignment="Top" Text="SAMPLE" Width="200" Height="100" />
        <TextBox x:Name="writeText" Drop="writeText_Drop" Width="200" Height="100" />
    </Grid>

I want to be able to drag and drop the textblock onto the textbox inside the grid so that the text gets copied from the source to the destination.