利用Spire插件给Word添加水印

            string wMarkText="水印";
            int wMarkFontSize = 46;
            string wMarkColor = "#736b6b";
            int wMarkLayout = 0;
            wMarkColor = wMarkColor.Substring(1);
                    #region 给Word文档添加水印
                    string path = "E:\TestFile\20191115033010124.docx";
                    //新建一个Document类对象，并加载需要添加水印的Word文档
                    Document doc = new Document();
                    //doc.LoadFromFile("E:\TestFile\20191115033010124.docx");
                    doc.LoadFromFile(path);

                    //新建一个TextWatermark对象，设置文本水印字样
                    TextWatermark txtWatermark = new TextWatermark();
                    txtWatermark.Text = wMarkText;

                    //设置文本水印字体大小、颜色和文本排列方式
                    txtWatermark.FontSize = wMarkFontSize;
                    txtWatermark.Color = Color.FromArgb(Convert.ToInt32("FF" + wMarkColor, 16));
                    if (wMarkLayout == 0)
                    {
                        txtWatermark.Layout = WatermarkLayout.Diagonal;
                    }
                    else
                    {
                        txtWatermark.Layout = WatermarkLayout.Horizontal;
                    }
                    //将文本应用到Word文档水印
                    doc.Watermark = txtWatermark;
                    //保存(替换原)文档
                    doc.SaveToFile(path, FileFormat.Docx2013);
                    return this.ApiResult("添加水印成功！");
                    #endregion