/// <summary>
/// 尝试生成元素开始标签的HTML形式
/// </summary>
/// <param name="element">要生成HTML的元素</param>
/// <param name="selfClosed">指示是否应产生自结束符号</param>
/// <returns></returns>
public static string GenerateTagHtml(IHtmlElement element, bool selfClosed)
{
if (element == null)
{
throw new ArgumentNullException("element");
}
var builder = new StringBuilder(20);
builder.Append("<");
builder.Append(element.Name);
foreach (var attribute in element.Attributes())
{
builder.Append(" ");
builder.Append(attribute.Name);
if (attribute.AttributeValue != null)
{
if ((HtmlSpecification.IsUriValue(attribute) || HtmlSpecification.IsScriptValue(attribute)) && !attribute.AttributeValue.Contains('"'))
{
builder.Append("=\"").Append(attribute.AttributeValue).Append("\"");
}
else
{
builder.Append("=\"").Append(HtmlEncoding.HtmlAttributeEncode(attribute.AttributeValue)).Append("\"");
}
}
}
if (selfClosed)
{
builder.Append(" /");
}
builder.Append(">");
return(builder.ToString());
}
/// <summary>
/// 将文档中所有的uri属性转换为绝对的uri。
/// </summary>
/// <param name="document">要执行转换的文档</param>
/// <param name="resolveInternalReference">是否转换页内 uri</param>
public static void ResolveUriToAbsoluate(this IHtmlDocument document, bool resolveInternalReference)
{
if (document == null)
{
throw new ArgumentNullException("document");
}
var baseUri = document.DocumentUri;
if (baseUri == null)
{
throw new InvalidOperationException();
}
foreach (var attribute in document.AllElements().SelectMany(e => e.Attributes()).Where(a => HtmlSpecification.IsUriValue(a)).ToArray())
{
var value = attribute.Value();
if (string.IsNullOrEmpty(value))
{
continue;
}
Uri uri;
if (!Uri.TryCreate(baseUri, value, out uri))
{
continue;
}
if (uri.Equals(baseUri) && !resolveInternalReference)
{
continue;
}
attribute.Element.SetAttribute(attribute.Name, uri.AbsoluteUri);
}
}