如何在Xamarin.Forms中连接字符串？

<Label Grid.Column="1" Grid.Row="1">
    <Label.FormattedText>
        <FormattedString>
            <Span TextColor="White" FontSize="18" Text="{Binding EMP_LAST_NAME'}"/>
            <Span TextColor="White" FontSize="18" Text="{Binding EMP_FIRST_NAME}"/>
        </FormattedString>
    </Label.FormattedText>
</Label>

https://stackoverflow.com/questions/38199133/how-to-concatenate-strings-in-xamarin-forms