C# 使用TWAIN协议进行扫描仪操作

折腾两台扫描仪程序的修改，今天有空把程序中涉及到扫描仪操作的代码贴出来，供大家一起交流学习。

public ArrayList TransferPictures()
        {
            ArrayList pics = new ArrayList();
            if (srcds.Id == IntPtr.Zero)
                return pics;

            TwRC rc;
            IntPtr hbitmap = IntPtr.Zero;
            TwPendingXfers pxfr = new TwPendingXfers();

            do
            {
                pxfr.Count = 0;
                hbitmap = IntPtr.Zero;

                TwImageInfo iinf = new TwImageInfo();//扫描仪设置的扫描图片信息

                rc = DSiinf(appid, srcds, TwDG.Image, TwDAT.ImageInfo, TwMSG.Get, iinf);//获取扫描图片信息
                if (rc != TwRC.Success)
                {
                    CloseSrc();
                    return pics;
                }


                rc = DSixfer(appid, srcds, TwDG.Image, TwDAT.ImageNativeXfer, TwMSG.Get, ref hbitmap);//扫描程序，如果扫描完成，则返回XferDone
                if (rc != TwRC.XferDone)
                {
                    CloseSrc();
                    return pics;
                }


                rc = DSpxfer(appid, srcds, TwDG.Control, TwDAT.PendingXfers, TwMSG.EndXfer, pxfr);//结束扫描
                if (rc != TwRC.Success)
                {
                    CloseSrc();
                    return pics;
                }

                pics.Add(hbitmap);
            }
            while (pxfr.Count != 0);

            rc = DSpxfer(appid, srcds, TwDG.Control, TwDAT.PendingXfers, TwMSG.Reset, pxfr);
            return pics;
        }