C#中將HTML匯總的相對URI更改為絕對URI

下面的代碼用以將給定的Html中的所有的URI，包括href和img都更改為絕對路徑
private static string ConvertToAbsoluteUrls (string Html, Uri relativeLocation) {
    IHTMLDocument2 doc = new HtmlDocumentClass ();
    doc.write (new object [] { Html });
    doc.close ();

    foreach (IHtmlAnchorElement anchor in doc.links) {
        IHTMLElement element = (IHtmlElement)anchor;
        string href = (string)element.getAttribute ("href", 2);
        if (href != null) {
            Uri addr = new Uri (relativeLocation, href);
            anchor.href = addr.AbsoluteUri;
        }
    }

    foreach (IHtmlImgElement image in doc.images) {
        IHTMLElement element = (IHtmlElement)image;
        string src = (string)element.getAttribute ("src", 2);
        if (src != null) {
            Uri addr = new Uri (relativeLocation, src);
            image.src = addr.AbsoluteUri;
        }
    }

    string ret = doc.body.innerHtml;

    return ret;
}