Removing Header and Footer

VSTO

Word.Document doc = Application.Documents.Open("Add Headers and Footers.doc");
Globals.ThisAddIn.Application.ActiveDocument.Sections[1].Headers[Microsoft.Office.Interop.Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.Paragraphs.Last.Range.Delete();
Globals.ThisAddIn.Application.ActiveDocument.Sections[1].Footers[Microsoft.Office.Interop.Word.WdHeaderFooterIndex.wdHeaderFooterPrimary].Range.Paragraphs.Last.Range.Delete();

Aspose.Words

Document doc = new Document("Remove Headers and Footers.doc");
foreach (Section section in doc)
{
	section.HeadersFooters.RemoveAt(0);
	HeaderFooter footer;

	// Primary footer is the footer used for odd pages.
	footer = section.HeadersFooters[HeaderFooterType.FooterPrimary];
	if (footer != null)
		footer.Remove();
}
doc.Save("Remove Headers and Footers.doc");

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