Question

我正在尝试使用iTextSharp

将网页图片添加到pdf中

我正在尝试使用与本地图像相同的代码

using (var pdfDoc = new Document()) 
using (var pdfWriter = PdfWriter.GetInstance(pdfDoc, pdfStream)) { 
    pdfDoc.Open();
    Image tif = Image.GetInstance("www.myimage.com");
    pdfDoc.Add(tif);
    pdfDoc.Close();
}

Answer 1

您必须先发送http网络请求才能下载图片。

public Image DownloadImageFromURL(string url)
{
   HttpWebRequest httpWebRequest = (HttpWebRequest)WebRequest.Create(filename);
   httpWebRequest.AllowWriteStreamBuffering = true;            
   httpWebRequest.UserAgent = "Mozilla/4.0 (compatible; MSIE 7.0; Windows NT 5.1)";            
   httpWebRequest.Timeout = 30000; //30 seconds
   webResponse = httpWebRequest.GetResponse();    
   webStream = webResponse.GetResponseStream();
   Image downloadImage = Image.FromStream(webStream);            
   webResponse.Close();   
   return downloadImage;
}

//in your code
    using (var pdfDoc = new Document()) 
using (var pdfWriter = PdfWriter.GetInstance(pdfDoc, pdfStream)) { 
    pdfDoc.Open();
    Image tif = DownloadImageFromURL("www.myimage.com");
    pdfDoc.Add(tif);
    pdfDoc.Close();
}

使用此方法制作HttpWebRequest并下载图像。现在将其写入pdf。

Answer 2

与其他发布的答案相反，您 NOT 需要发出单独的HTTP请求。只需确保在致电Image.GetInstance()时使用an absolute URI：

string url = "http://upload.wikimedia.org/wikipedia/commons/thumb/8/8f/Pollinationn.jpg/320px-Pollinationn.jpg";
using (Document document = new Document()) {
  PdfWriter.GetInstance(document, Response.OutputStream);
  document.Open();
  Image img = Image.GetInstance(url);
  document.Add(img);
}

这是clearly documented for the overloaded method call。

将网页图片添加到pdf

2 个答案: