WPF: Multibinding with string literal and property in a trigger

Question

I'm trying to set a TextBlock.Text in a trigger. Everything works fine if I bind property in the setter, but how do I "concat" a string and a property?
For instance, I've got a Date property. I want the text to be "The date is 9/21/2017."
So far, I managed to show "9/21/2017", but can't figure out how to concat a string before it (I present you only the "interesting part"):

<DataTrigger Binding="{Binding State}" Value="{x:Static model:Croissant+CroissantState.IsUsed}">
    <Setter Property="Text">
        <Setter.Value>
            <MultiBinding StringFormat="{}{0:d}">
                <Binding Path="Date" />
            </MultiBinding>
        </Setter.Value>
    </Setter>
</DataTrigger>

Any advice on how to bind a string literal? Do I have to use a converter for this or is there an "easy way"?

Answer 1

For anyone who doesn't read the comment, and thanks to Ayyappan Subramanian, the solution is:

<DataTrigger Binding="{Binding State}" Value="{x:Static model:Croissant+CroissantState.IsUsed}">
    <Setter Property="Text">
        <Setter.Value>
            <Binding Path="Date" StringFormat="The date is {0:d}" />
        </Setter.Value>
    </Setter>
</DataTrigger>