Question

How can I prefix bound values in TextBlock controls in a StackPanel without using separate controls for the prefixes?

E.g., let’s say I have a dialog that uses a TreeView to display a list of books, with the top nodes being the title, and a set of subordinate nodes for the other book attributes (ISBN, Author, etc.).

I have the binding working correctly, but my user wants the book attributes list to stack vertically, and, obviously, he wants each attribute node to have a descriptive prefix before the value (e.g., “Author: Erich Gamma” instead of just “Erich Gamma”). Inside my HDT and DT elements, I am using a StackPanel and TextBlock controls to display the values.

Must I use a separate TextBlock control for the prefix of each attribute

<!-- Works, but requires 2 controls to display the book author and the prefix stacks above the author -->
<TextBlock Text="Author: "/><TextBlock Text="{Binding Path=Author}" />  

or is there a way to do this with a single TextBlock control for each node?

<!-- only one control, but doesn't work -->
<TextBlock Text="Author:  {Binding Path=Author}" />  

I know this must be a common issue, and I Googled for it and searched in the three WPF books I have, but I guess I don’t know the right way to search for what I’m trying to say.

Thanks!

Answer 1

If you have .Net 3.5 SP1, you can easily achive this via StringFormat

<TextBlock Text="{Binding Path=Title, StringFormat= Title: {0}}" />

You can also do this

<TextBlock>
  <TextBlock.Text>
    <MultiBinding StringFormat="Author: {0}, Title: {1}">
      <Binding Path="Author"/>
      <Binding Path="Title"/>
    </MultiBinding>
  </TextBlock.Text>
</TextBlock>

If you are not using SP1,
Then you can use a ValueConverter