正则表达式分组

input：.*?)"

pattern：value

Match match = Regex.Match(input, pattern);
return match.Success ? match.Groups[key].Value : string.Empty;

    "utf-8">
    "viewport"
        content="width=device-width,initial-scale=1,minimum-scale=1,maximum-scale=1,user-scalable=no" />
    
    
    "stylesheet" href="https://g.alicdn.com/bsop-static/sufei-punish/0.0.142/build/main.css">