Convert doc documents to Rich Text Format [C #]

The conversion first adds a reference to the Microsoft Word 9.0 Object Library in the project reference.

Using System;

Namespace Docconvert

{
Class Doctortf
{
static void Main ()
{

Create an instance of Word
Word.Application Newapp = new Word.Application ();

Specify source and destination files
Object Source= "C:\\abc\\source.doc";
Object target= "C:\\abc\\target.rtf";

Object Unknown =type.missing;

Open the Word file you want to convert
NewApp.Documents.Open (ref Source,ref Unknown,
Ref Unknown,ref Unknown,ref Unknown,
Ref Unknown,ref Unknown,ref Unknown,
Ref Unknown,ref Unknown,ref Unknown,
Ref Unknown);

Specify the type of document
Object format = Word.WdSaveFormat.wdFormatRTF;

Change Document Type
NewApp.ActiveDocument.SaveAs (ref target,ref format,
Ref Unknown,ref Unknown,ref Unknown,
Ref Unknown,ref Unknown,ref Unknown,
Ref unknown,ref unknown,ref Unknown);

Close Word Instance
Newapp.quit (ref unknown,ref unknown,ref Unknown);

}
}
}