How to get Numbered Heading list in word using VSTO.

Question

I can get only heading without Number.

 

Here is my code.

 

Selection wordSelection = Globals.ThisAddIn.Application.Selection;

wordSelection.set_Style(WdBuiltinStyle.wdStyleHeading1);

 

But How can I get Numbered Headings. Please anyone can send me the code.It is urgent for me now..

I want like

 

1 Heading

 

   1.1   Heading

 

           1.1.1 Heading 

 

Like this Please send me the code..I am wating.