C# 实现HTML转换成图片的方法

/// <summary>
        /// 通过WebBrowser控件来实现从HTML到Bmp图片的生成。
        /// </summary>
        /// <param name="htmPath">HTML路径</param>
        /// <returns>Bmp图片路径</returns>
        private static string ConverHTML(string htmPath)
        {
            string ImagePath = string.Empty;
            WebBrowser web = new WebBrowser();
            web.Navigate(htmPath);
            while (web.ReadyState != WebBrowserReadyState.Complete)
            {
                System.Windows.Forms.Application.DoEvents();
            }
            Rectangle screen = Screen.PrimaryScreen.Bounds;
            Size? imgsize = null;
            //set the webbrowser width and hight
            web.Width = screen.Width;
            web.Height = screen.Height;
            //suppress script errors and hide scroll bars
            web.ScriptErrorsSuppressed = true;
            web.ScrollBarsEnabled = false;
            Rectangle body = web.Document.Body.ScrollRectangle;

//check if the document width/height is greater than screen width/height
            Rectangle docRectangle = new Rectangle()
            {
                Location = new Point(0, 0),
                Size = new Size(body.Width > screen.Width ? body.Width : screen.Width,
                 body.Height > screen.Height ? body.Height : screen.Height)
            };
            //set the width and height of the WebBrowser object
            web.Width = docRectangle.Width;
            web.Height = docRectangle.Height;

//if the imgsize is null, the size of the image will
            //be the same as the size of webbrowser object
            //otherwise  set the image size to imgsize
            Rectangle imgRectangle;
            if (imgsize == null)
                imgRectangle = docRectangle;
            else
                imgRectangle = new Rectangle()
                {
                    Location = new Point(0, 0),
                    Size = imgsize.Value
                };
            //create a bitmap object
            Bitmap bitmap = new Bitmap(imgRectangle.Width - 24, imgRectangle.Height);
            //get the viewobject of the WebBrowser
            IViewObject ivo = web.Document.DomDocument as IViewObject;

using (Graphics g = Graphics.FromImage(bitmap))
            {
                //get the handle to the device context and draw
                IntPtr hdc = g.GetHdc();
                ivo.Draw(1, -1, IntPtr.Zero, IntPtr.Zero,
                         IntPtr.Zero, hdc, ref imgRectangle,
                         ref docRectangle, IntPtr.Zero, 0);
                g.ReleaseHdc(hdc);
            }
            SAVEWORDJPG = string.Format(@"E:\cheng_Text\FormatApplication\测试文件\{0}.bmp", Guid.NewGuid().ToString());
            bitmap.Save(SAVEWORDJPG, System.Drawing.Imaging.ImageFormat.Bmp);
            bitmap.Dispose();
            web.Dispose();
            DeleteTempFile(TEMPHTMLPATH);
            return SAVEWORDJPG;
        }

/// <summary>
        /// 删除指定的临时文件。
        /// </summary>
        /// <param name="filePath"></param>
        private static void DeleteTempFile(string filePath)
        {
            //删除临时HTML文件 。
            File.Delete(filePath);
            //删除目录文件内容。
            string[] files = filePath.Split('.');
            if (files[1].ToLower().Equals("htm"))
            {
                string dirPath = files[0] + ".files";
                foreach (string f in Directory.GetFileSystemEntries(dirPath))
                {
                    // 如果是文件存在 
                    if (File.Exists(f))
                    {
                        FileInfo fi = new FileInfo(f);
                        if (fi.Attributes.ToString().IndexOf("Readonly") != 1)
                        {
                            fi.Attributes = FileAttributes.Normal;
                        }
                        // 直接删除其中的文件 
                        File.Delete(f);
                    }
                }
                Directory.Delete(dirPath);
            }
        }

#region==========IViewObje【实现接口类】================
        [ComVisible(true), ComImport()]
        [GuidAttribute("0000010d-0000-0000-C000-000000000046")]
        [InterfaceTypeAttribute(ComInterfaceType.InterfaceIsIUnknown)]
        public interface IViewObject
        {
            [return: MarshalAs(UnmanagedType.I4)]
            [PreserveSig]
            int Draw(
                [MarshalAs(UnmanagedType.U4)] UInt32 dwDrawAspect,
                int lindex,
                IntPtr pvAspect,
                [In] IntPtr ptd,
                IntPtr hdcTargetDev,
                IntPtr hdcDraw,
                [MarshalAs(UnmanagedType.Struct)] ref Rectangle lprcBounds,
                [MarshalAs(UnmanagedType.Struct)] ref Rectangle lprcWBounds,
                IntPtr pfnContinue,
                [MarshalAs(UnmanagedType.U4)] UInt32 dwContinue);
            [PreserveSig]
            int GetColorSet([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect,
               int lindex, IntPtr pvAspect, [In] IntPtr ptd,
                IntPtr hicTargetDev, [Out] IntPtr ppColorSet);
            [PreserveSig]
            int Freeze([In, MarshalAs(UnmanagedType.U4)] int dwDrawAspect,
                            int lindex, IntPtr pvAspect, [Out] IntPtr pdwFreeze);
            [PreserveSig]
            int Unfreeze([In, MarshalAs(UnmanagedType.U4)] int dwFreeze);
            void SetAdvise([In, MarshalAs(UnmanagedType.U4)] int aspects,
              [In, MarshalAs(UnmanagedType.U4)] int advf,
              [In, MarshalAs(UnmanagedType.Interface)] IAdviseSink pAdvSink);
            void GetAdvise([In, Out, MarshalAs(UnmanagedType.LPArray)] int[] paspects,
              [In, Out, MarshalAs(UnmanagedType.LPArray)] int[] advf,
              [In, Out, MarshalAs(UnmanagedType.LPArray)] IAdviseSink[] pAdvSink);
        }
        #endregion