如何將 web 頁面保存到圖像

Question

我有一個 WebBrowser 控件，我想將查看的整個頁面保存為圖像（任何 web 頁面）。 我嘗試使用 IHTMLElementRender 界面，但它不適用於所有 web 頁面。 也許我做錯了什么，因為有時快照包括滾動條，有時它只是部分的。 您是否有可以將整個 web 頁面保存到圖像的工作示例？

謝謝。

Answer 1

有一篇很棒的 CodeProject 文章展示了如何使用 IE 引擎完成這項任務。 如果您更喜歡使用其他瀏覽器的渲染引擎，這是一個開始學習的好地方。 Firefox 還有一個插件可以做到這一點，您可以深入了解它的內部結構，以了解如何在 firefox 中實現這一點。

Answer 2

見http://blog.ashmind.com/index.php/2008/09/28/putting-web-snapshots-to-practical-use/這里是代碼： http://ashmind-web-ui.googlecode .com/svn/trunk/AshMind.Web.Snapshots/

它應該在大多數情況下正確識別尺寸，但它絕不是經過完全測試的最終解決方案。

Answer 3

如果網頁在 JS 上很重，例如地圖應用程序，則提供的解決方案將無法很好地工作。

發現此代碼與 Webbrowser 控件一起使用更高效，在缺乏更好的...

private void waitTillLoad(WebBrowser webBrowser1)
{
   WebBrowserReadyState loadStatus;

   //wait till beginning of loading next page 
   int waittime = 100000;
   int counter = 0;
   while (true)
   {
       loadStatus = webBrowser1.ReadyState;
       Application.DoEvents();

       if ((counter > waittime) || (loadStatus == WebBrowserReadyState.Uninitialized) || (loadStatus == WebBrowserReadyState.Loading) || (loadStatus == WebBrowserReadyState.Interactive))
       {
           break;
       }
       counter++;
   }

   //wait till the page get loaded.
   counter = 0;
   while (true)
   {
       loadStatus = webBrowser1.ReadyState;
       Application.DoEvents();

       if (loadStatus == WebBrowserReadyState.Complete)
       {
           break;
       }
       counter++;

   }
}

歸功於http://qualitypoint.blogspot.com/2009/03/c-webbrowser-control-synchronization.html的 QualityPoint Technologies

！

問候， byte_slave

Answer 4

您可以使用這些家伙http://webthumb.bluga.net/home和以下代碼。 如果您只需要每月生成幾張圖像，它是免費的，但它們會收取更多費用。

（我與他們沒有任何關系，我過去只是使用過這個）

public enum OutputType
    {
        Png,
        Jpg
    }

    public interface IWebThumbAPI
    {
        int Delay { get; set; }
        int Width { get; set; }
        int Height { get; set; }
        OutputType OutputType { get; set; }
        WebThumbAPI Get(string url);
        WebThumbAPI Get(string url, int x, int y, int width, int height);
        System.Drawing.Image SaveSize(WebThumbSize webThumbSize);
    }

    public class WebThumbAPI : IWebThumbAPI
    {
        private readonly string apiKey;
        private IList<WebThumbResponse> webThumbResponse;
        private string jobId;
        private string ApiUrl { get; set; }
        public int Delay { get; set; }
        public int Width { get; set; }
        public int Height { get; set; }
        public OutputType OutputType { get; set; }

        public WebThumbAPI(string apiKey)
            : this(apiKey, "")
        {
        }

        public WebThumbAPI(string apiKey, string jobId)
        {
            this.apiKey = apiKey;
            OutputType = OutputType.Png;
            Width = 1024;
            Height = 768;
            Delay = 5;
            ApiUrl = "http://webthumb.bluga.net/api.php";
            this.jobId = jobId;
        }

        public WebThumbAPI Get(string url)
        {
            return Get(url, 0, 0, 400, 200);
        }

        public WebThumbAPI Get(string url, int x, int y, int width, int height)
        {
            var outputType = OutputType == OutputType.Jpg ? "jpg" : "png";

            var doc = new XDocument(
                new XElement("webthumb",
                            new XElement("apikey", apiKey),
                             new XElement("request",
                                                 new XElement("url", url),
                                                 new XElement("outputType", outputType),
                                                 new XElement("width", Width),
                                                 new XElement("height", Height),
                                                 new XElement("delay", Delay),
                                                 new XElement("excerpt",
                                                     new XElement("x", x),
                                                     new XElement("y", y),
                                                     new XElement("width", width),
                                                     new XElement("height", height)))
                    )
                );

            var request = getRequest(doc.ToString());
            var webResponse = (HttpWebResponse)request.GetResponse();
            if (webResponse.ContentType == "text/xml")
            {
                var stream = webResponse.GetResponseStream();
                var response = XDocument.Load(XmlReader.Create(stream));
                webThumbResponse = (from xml in response.Descendants("job")
                                    select new WebThumbResponse
                                    {
                                        Estimate = (int)xml.Attribute("estimate"),
                                        Time = (DateTime)xml.Attribute("time"),
                                        Url = (string)xml.Attribute("url"),
                                        Cost = (int)xml.Attribute("cost"),
                                        Job = (string)xml.Value
                                    }).ToList();
                stream.Close();
                if (webThumbResponse.Count == 0)
                    jobId = "-1";
                else
                {
                    jobId = webThumbResponse[0].Job;
                    Thread.Sleep(webThumbResponse[0].Estimate * 1000);
                }

            }
            else
            {
                throw new InvalidOperationException("Failed request");
            }
            return this;
        }

        public System.Drawing.Image SaveSize(WebThumbSize webThumbSize)
        {
            if (jobId == "-1")
                return defaultImage(webThumbSize);
            var doc = new XDocument(
                new XElement("webthumb",
                            new XElement("apikey", apiKey),
                             new XElement("fetch",
                                                 new XElement("job", jobId),
                                                 new XElement("size", Enum.GetName(typeof(WebThumbSize), webThumbSize).ToLower())
                                                 )
                    )
                );
            var request = getRequest(doc.ToString());
            var webResponse = (HttpWebResponse)request.GetResponse();
            var stream = webResponse.GetResponseStream();

            Image image = null;
            try
            {
                image = System.Drawing.Image.FromStream(stream);
            }
            catch
            {
                image = defaultImage(webThumbSize);

            }
            return image;
        }

        private Image defaultImage(WebThumbSize webThumbSize)
        {
            var s = getSize(webThumbSize);
            var b = new Bitmap(s.Width, s.Height);
            var im = Image.FromHbitmap(b.GetHbitmap());
            var gr = System.Drawing.Graphics.FromImage(im);
            gr.Clear(Color.White);
            gr.Dispose();
            return im;
        }

        private static System.Drawing.Size getSize(WebThumbSize size)
        {
            switch (size)
            {
                case WebThumbSize.Small:
                    return new Size(80, 60);
                case WebThumbSize.Excerpt:
                    return new Size(400, 200);
                default:
                    return new Size(1, 1);
            }
        }

        private HttpWebRequest getRequest(string xml)
        {
            var request = (HttpWebRequest)WebRequest.Create(ApiUrl);
            request.Method = "POST";
            request.Timeout = 20000;
            request.ContentType = "text/xml";
            request.UserAgent = @"Mozilla/5.0 (Macintosh; U; PPC Mac OS X; en) AppleWebKit/418.8 (KHTML, like Gecko) Safari/419.3";
            request.KeepAlive = false;
            request.Pipelined = false;

            Stream newStream = request.GetRequestStream();
            var encoding = new ASCIIEncoding();
            byte[] data = encoding.GetBytes(xml);
            newStream.Write(data, 0, data.Length);
            newStream.Close();
            return request;
        }
    }

    public class WebThumbResponse
    {
        public DateTime Time;
        public string Job;
        public string Url;
        public int Cost;
        public int Estimate { get; set; }
    }

    public enum WebThumbSize
    {
        Small,
        Medium,
        Medium2,
        Large,
        Excerpt
    }