Чтение текста из Word .docx

using Word = Microsoft.Office.Interop.Word;
using Office = Microsoft.Office.Core;

    object file = Path.GetDirectoryName(Application.ExecutablePath) + @"\Answer.doc";
 
    Word.Application wordObject = new Word.ApplicationClass();
    wordObject.Visible = false;
 
    object nullobject = Missing.Value;
    Word.Document docs = wordObject.Documents.Open
        (ref file, ref nullobject, ref nullobject, ref nullobject,
        ref nullobject, ref nullobject, ref nullobject, ref nullobject,
        ref nullobject, ref nullobject, ref nullobject, ref nullobject,
        ref nullobject, ref nullobject, ref nullobject, ref nullobject);
 
    String strLine;
    bool bolEOF = false;
 
    docs.Characters[1].Select();
 
    int index = 0;
    do
    {
        object unit = Word.WdUnits.wdLine;
        object count = 1;
        wordObject.Selection.MoveEnd(ref unit, ref count);
 
        strLine = wordObject.Selection.Text;
        richTextBox1.Text += ++index + " - " + strLine + "\r\n"; //for our understanding
 
        object direction = Word.WdCollapseDirection.wdCollapseEnd;
        wordObject.Selection.Collapse(ref direction);
 
        if (wordObject.Selection.Bookmarks.Exists(@"\EndOfDoc"))
            bolEOF = true;
    } while (!bolEOF);
 
    docs.Close(ref nullobject, ref nullobject, ref nullobject);
    wordObject.Quit(ref nullobject, ref nullobject, ref nullobject);
    docs = null;
    wordObject = null;