public static void ReplaceText()
{
WordFile wordFile = new WordFile();
WordDocument document = wordFile.Import(File.ReadAllBytes("Sample.docx"));
WordDocumentBuilder builder = new WordDocumentBuilder(document);
//Replace target text in whole document, match-case and match-whole-word are supported
builder.ReplaceText("Page", "as", true, true);
File.WriteAllBytes("ReplaceText.docx", wordFile.Export(document));
}