c#中Word操作

///

/// 添加Word文件，返回文件内容string
///

///
///
public string AddWord(object fileName)
{
    string fileContent = "";
    Word.ApplicationClass app = new Word.ApplicationClass();
    Word.Document doc = null;
    object missing = System.Reflection.Missing.Value;
    object readOnly = false;
    object isVisible = false;

    try
    {
        doc = app.Documents.Open(ref fileName,ref missing,ref readOnly,ref missing,ref missing,ref missing,ref missing,ref missing,ref missing,ref missing,ref missing,ref isVisible,ref missing,ref missing,ref missing,ref missing);
        doc.ActiveWindow.Selection.WholeStory();
        doc.ActiveWindow.Selection.Copy();

        IDataObject data = Clipboard.GetDataObject();
        fileContent = data.GetData(DataFormats.Text).ToString();
    }
    finally
    {
        if (doc != null)
        {
            doc.Close(ref missing,ref missing,ref missing);
            doc = null;
        }
        if (doc == null)
        {
            app.Quit(ref missing,ref missing,ref missing);
            app = null;
        }
    } 
    return fileContent;
}