目前我使用的.Net WebBrowser.Document.Images（）做到这一点。它要求 Webrowser 加载文档。它的混乱，占用资源。

Currently I use .Net WebBrowser.Document.Images() to do this. It requires the Webrowser to load the document. It's messy and takes up resources.

据this XPath的问题比一个正则表达式，在这更好的。

According to this question XPath is better than a regex at this.

任何人都知道如何做到这一点在C＃？

Anyone know how to do this in C#?

推荐答案

如果你输入的字符串是有效的XHTML，你可以把是为XML，将其加载到一个XmlDocument，并做XPath的魔法:)但它并非总是如此。

If your input string is valid XHTML you can treat is as xml, load it into an xmldocument, and do XPath magic :) But it's not always the case.

否则，你可以试试这个功能，这将返回来自HtmlSource所有图片链接：

Otherwise you can try this function, that will return all image links from HtmlSource :

public List<Uri> FetchLinksFromSource(string htmlSource)
{
    List<Uri> links = new List<Uri>();
    string regexImgSrc = @"<img[^>]*?srcs*=s*[""']?([^'"" >]+?)[ '""][^>]*?>";
    MatchCollection matchesImgSrc = Regex.Matches(htmlSource, regexImgSrc, RegexOptions.IgnoreCase | RegexOptions.Singleline);
    foreach (Match m in matchesImgSrc)
    {
        string href = m.Groups[1].Value;
        links.Add(new Uri(href));
    }
    return links;
}

和您可以使用它是这样的：

And you can use it like this :

HttpWebRequest request = (HttpWebRequest)WebRequest.Create("http://www.example.com");
request.Credentials = System.Net.CredentialCache.DefaultCredentials;
HttpWebResponse response = (HttpWebResponse)request.GetResponse();
if (response.StatusCode == HttpStatusCode.OK)
{
    using( StreamReader sr = new StreamReader( response.GetResponseStream() )
    {
        List<Uri> links = FetchLinksFromSource( sr.ReadToEnd() );
    }
}