Question

我正在使用Jeff Atwood的代码here

来清理我的Html

但我遇到的问题是当我将Markdown链接输入表单时（它们被删除）

<http://www.example.com>

这是我正在使用的代码。

private static Regex _tags = new Regex("<[^>]*(>|$)",
    RegexOptions.Singleline | RegexOptions.ExplicitCapture | RegexOptions.Compiled);
private static Regex _whitelist = new Regex(@"
    ^</?(b(lockquote)?|code|d(d|t|l|el)|em|h(1|2|3)|i|kbd|li|ol|p(re)?|s(ub|up|trong|trike)?|ul)>$|
    ^<(b|h)r\s?/?>$",
    RegexOptions.Singleline | RegexOptions.ExplicitCapture | RegexOptions.Compiled | RegexOptions.IgnorePatternWhitespace);
private static Regex _whitelist_a = new Regex(@"
    ^<a\s
    href=""(\#\d+|(https?|ftp)://[-a-z0-9+&@#/%?=~_|!:,.;\(\)]+)""
    (\stitle=""[^""<>]+"")?\s?>$|
    ^</a>$",
    RegexOptions.Singleline | RegexOptions.ExplicitCapture | RegexOptions.Compiled | RegexOptions.IgnorePatternWhitespace);
private static Regex _whitelist_img = new Regex(@"
    ^<img\s
    src=""https?://[-a-z0-9+&@#/%?=~_|!:,.;\(\)]+""
    (\swidth=""\d{1,3}"")?
    (\sheight=""\d{1,3}"")?
    (\salt=""[^""<>]*"")?
    (\stitle=""[^""<>]*"")?
    \s?/?>$",
    RegexOptions.Singleline | RegexOptions.ExplicitCapture | RegexOptions.Compiled | RegexOptions.IgnorePatternWhitespace);


/// <summary>
/// sanitize any potentially dangerous tags from the provided raw HTML input using 
/// a whitelist based approach, leaving the "safe" HTML tags
/// CODESNIPPET:4100A61A-1711-4366-B0B0-144D1179A937
/// </summary>
public static string Sanitize(string html)
{
    if (String.IsNullOrEmpty(html)) return html;

    string tagname;
    Match tag;

    // match every HTML tag in the input
    MatchCollection tags = _tags.Matches(html);
    for (int i = tags.Count - 1; i > -1; i--)
    {
        tag = tags[i];
        tagname = tag.Value.ToLowerInvariant();

        if(!(_whitelist.IsMatch(tagname) || _whitelist_a.IsMatch(tagname) || _whitelist_img.IsMatch(tagname)))
        {
            html = html.Remove(tag.Index, tag.Length);
            System.Diagnostics.Debug.WriteLine("tag sanitized: " + tagname);
        }
    }

    return html;
}

Answer 1

是的，因为那不是有效的HTML ...因此代码正在做它声称要做的事情。

由于Markdown允许嵌入式HTML，但HTML不允许（所有形式）嵌入Markdown，我建议您首先将Markdown转换为HTML，然后然后清理它...

使用Jeff Atwood的示例清理HTML

1 个答案: