关于c#转换word到图片的问题，有源码，有测试数据，结果不满意，百思不得解，谢谢回答

using System;

using System.Collections.Generic;

using System.Linq;

using System.Text;

using System.Threading.Tasks;

using Microsoft.Office.Interop.Word;

using System.Drawing.Imaging;

using System.Drawing;

using System.IO;

using System.Drawing.Drawing2D;

using System.Windows.Forms;



namespace ConsoleApplication3

{

    class Program

    {

        static void Main(string[] args)

        {

            //运行13版本word，请改一下引用的两个dll到dll的15版本，图片是透明的，想要不透明，转换成jpg即可

         

            ConvertWord2Png("c:\\2.docx", "d:\\");

            Console.WriteLine("已完成");

            Console.ReadKey();

        }



        private static void ConvertWord2Png(string wordFile,string destinationFileDirectory)

        {

            Microsoft.Office.Interop.Word.Application app = new Microsoft.Office.Interop.Word.Application();

            Document doc = null;

            object unknow = Type.Missing;

            app.Visible = false;

            object file = wordFile;

            doc = app.Documents.Open(ref file,

                ref unknow, ref unknow, ref unknow, ref unknow,

                ref unknow, ref unknow, ref unknow, ref unknow,

                ref unknow, ref unknow, ref unknow, ref unknow,

                ref unknow, ref unknow, ref unknow);





            //获取总页数

            int pages = doc.ComputeStatistics(WdStatistic.wdStatisticPages, ref  unknow);

            object What = Microsoft.Office.Interop.Word.WdGoToItem.wdGoToPage;

            object Which = Microsoft.Office.Interop.Word.WdGoToDirection.wdGoToNext;





            for (int i = 1; i < pages + 1; i++)

            {

                object page = i + ""; // 页数 



                Microsoft.Office.Interop.Word.Range ran1 = doc.GoTo(ref What, ref Which, ref page, ref unknow);



                Microsoft.Office.Interop.Word.Range ran2 = ran1.GoToPrevious(Microsoft.Office.Interop.Word.WdGoToItem.wdGoToPage);



                object start = ran2.End;

                object end = ran1.Start;

                Range ran3 = doc.Range(ref start, ref end);

                if (i == pages)//最后一页处理

                {

                    ran3 = doc.Range(ref end);

                }

                string x = ran3.Text;

                SaveRangeToPng(ran3, destinationFileDirectory+ i + ".png");

            }

            doc.Close();

        }

        /// <summary>

        /// 把word文档的一个范围存储成png图片

        /// </summary>

        /// <param name="range"></param>

        private static void SaveRangeToPng(Range range, string saveFilePath)

        {

            byte[] bt = (byte[])range.EnhMetaFileBits;

            FileStream fs = new FileStream(saveFilePath, FileMode.Create);

            fs.Write(bt, 0, bt.Count());

            fs.Close();

           //用range.copytoPicture方法内存中找不到，所以用直接储存方式。

        }

    }

}