Replace Field in Header&Footer in Word Using Interop

Question

How to replace a \"FIELD\" in the header/footer?

Ex: Word doc file with File Name & Date. in place of file path - [FilePath] instead C://Documents/Location/Filen

Answer 1

Finally after going through the poor documentation about introp.word, got the solution

// Loop through all sections
foreach (Microsoft.Office.Interop.Word.Section section in wordDocument.Sections) {

    wordDocument.TrackRevisions = false; //Disable Tracking for the Field replacement operation

    //Get all Headers
    Microsoft.Office.Interop.Word.HeadersFooters headers = section.Headers;

    //Section headerfooter loop for all types enum WdHeaderFooterIndex. wdHeaderFooterEvenPages/wdHeaderFooterFirstPage/wdHeaderFooterPrimary;                          
    foreach (Microsoft.Office.Interop.Word.HeaderFooter header in headers)
    {
        Fields fields = header.Range.Fields;

        foreach (Field field in fields)
        {
            if (field.Type == WdFieldType.wdFieldDate)
            {
                field.Select ();
                field.Delete ();
                wordApplication.Selection.TypeText ("[DATE]");
            }
            else if (field.Type == WdFieldType.wdFieldFileName)
            {
                field.Select ();
                field.Delete ();
                wordApplication.Selection.TypeText ("[FILE NAME]");

            }
        }
    }

    //Get all Footers
    Microsoft.Office.Interop.Word.HeadersFooters footers = section.Footers;

    //Section headerfooter loop for all types enum WdHeaderFooterIndex. wdHeaderFooterEvenPages/wdHeaderFooterFirstPage/wdHeaderFooterPrimary; 
    foreach (Microsoft.Office.Interop.Word.HeaderFooter footer in footers)
    {
        Fields fields = footer.Range.Fields;

        foreach (Field field in fields)
        {
            if (field.Type == WdFieldType.wdFieldDate)
            {
                field.Select ();
                field.Delete ();
                wordApplication.Selection.TypeText ("[DATE]");
            }
            else if (field.Type == WdFieldType.wdFieldFileName)
            {
                field.Select ();
                field.Delete ();
                wordApplication.Selection.TypeText ("[FILE NAME]");

            }
        }
    }
}