/// <summary>
/// Associate an HTML tag with an HtmlElementCreator delegate used to
/// construct a corresponding derived HtmlElement instance
/// </summary>
/// <param name="tag">HTML tag</param>
/// <param name="creator">
/// HtmlElementCreator used to create an HtmlElement for this type of tag
/// </param>
public static void Register(string tag, HtmlElementCreator creator)
{
// Ensure parameters
if (tag == null)
{
throw new ArgumentNullException("tag", "tag cannot be null!");
}
if (string.IsNullOrEmpty(tag))
{
throw new ArgumentException("tag cannot be empty!", "tag");
}
if (creator == null)
{
throw new ArgumentNullException("creator", "creator cannot be null!");
}
// Add the tag to the element factory
_elementFactory[tag] = creator;
}
/// <summary>
/// Create a new HtmlElement
/// </summary>
/// <param name="tag">HTML tag of the element</param>
/// <param name="attributes">Attributes defined on the element</param>
/// <param name="parent">Parent HtmlElement</param>
/// <param name="page">Page containing the element</param>
/// <returns>HtmlElement</returns>
internal static HtmlElement Create(string tag, IDictionary <string, string> attributes, HtmlElement parent, HtmlPage page)
{
HtmlElement element = null;
// Try to use an HtmlElementCreator
HtmlElementCreator creator = null;
if (_elementFactory.TryGetValue(tag, out creator))
{
// Ignore any exceptions raised during creation
try { element = creator(tag, attributes, parent, page); }
catch { }
}
// If we don't have a creator for the element or it failed to create,
// create a default HtmlElement
if (element == null)
{
element = new HtmlElement(tag, attributes, parent, page);
}
return(element);
}
