Word.Application word = new Word.Application();
Word.Document doc = new Word.Document();
object fileName = @"C:wordFile.docx";
object missing = System.Type.Missing;
doc = word.Documents.Open(ref fileName,
ref missing, ref missing, ref missing, ref missing,
ref missing, ref missing, ref missing, ref missing,
ref missing, ref missing, ref missing, ref missing,
ref missing, ref missing, ref missing);
string ReadValue = string.Empty;
doc.Activate();
foreach (Word.Range tmpRange in doc.StoryRanges)
{
ReadValue += tmpRange.Text;
}