Image Tag的src使用Regex

Question

我需要使用正则表达式找到第一个 img标记的src 到以下字符串。 怎么做？

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Answer 1

Don't use Regex to parse html。使用真正的html解析器，如HtmlAgilityPack

var html = WebUtility.HtmlDecode(yourtext);
var doc = new HtmlAgilityPack.HtmlDocument();
doc.LoadHtml(html);
var urls = doc.DocumentNode.SelectNodes("//img[@src]")
              .Select(img => img.Attributes["src"].Value)
              .ToList(); 

Answer 2

试试这个

<img.+?src=[\"'](.+?)[\"'].*?>

string src = Regex.Match(original_text, "<img.+?src=[\"'](.+?)[\"'].*?>", RegexOptions.IgnoreCase).Groups[1].Value;

Regex Demo