private void LazyLoadDtd(Uri baseUri)
{
if (this.m_dtd == null && !this.m_ignoreDtd)
{
if (string.IsNullOrEmpty(this.m_syslit))
{
if (this.m_docType != null && StringUtilities.EqualsIgnoreCase(this.m_docType, "html"))
{
Assembly a = typeof(SgmlReader).GetTypeInfo().Assembly;
string name = a.FullName.Split(',')[0] + ".Html.dtd";
Stream stm = a.GetManifestResourceStream(name);
if (stm != null)
{
StreamReader sr = new StreamReader(stm);
this.m_dtd = SgmlDtd.Parse(baseUri, "HTML", sr, null, this.m_proxy, null);
}
}
}
else
{
if (baseUri != null)
{
baseUri = new Uri(baseUri, this.m_syslit);
}
else if (this.m_baseUri != null)
{
baseUri = new Uri(this.m_baseUri, this.m_syslit);
}
else
{
#if PORTABLE
throw new InvalidOperationException("Cannot load DTD without specifying base URI.");
#else
baseUri = new Uri(new Uri(Directory.GetCurrentDirectory() + "/"), this.m_syslit);
#endif
}
this.m_dtd = SgmlDtd.Parse(baseUri, this.m_docType, this.m_pubid, baseUri.AbsoluteUri, this.m_subset, this.m_proxy, null);
}
}
if (this.m_dtd != null && this.m_dtd.Name != null)
{
switch (this.CaseFolding)
{
case CaseFolding.ToUpper:
this.m_rootElementName = this.m_dtd.Name.ToUpperInvariant();
break;
case CaseFolding.ToLower:
this.m_rootElementName = this.m_dtd.Name.ToLowerInvariant();
break;
default:
this.m_rootElementName = this.m_dtd.Name;
break;
}
this.m_isHtml = StringUtilities.EqualsIgnoreCase(this.m_dtd.Name, "html");
}
}
public static SgmlDtd Parse(Uri baseUri, string name, TextReader input, string subset, string proxy, XmlNameTable nt)
{
SgmlDtd dtd = new SgmlDtd(name, nt);
dtd.PushEntity(baseUri, new Entity(dtd.Name, baseUri, input, proxy));
if (!string.IsNullOrEmpty(subset))
{
dtd.PushEntity(baseUri, new Entity(name, subset));
}
try
{
dtd.Parse();
}
catch (Exception e)
{
throw new SgmlParseException(e.Message + dtd.m_current.Context());
}
return dtd;
}
/// <summary>
/// Checks whether an element using this group can contain a specified element.
/// </summary>
/// <param name="name">The name of the element to look for.</param>
/// <param name="dtd">The DTD to use during the checking.</param>
/// <returns>true if an element using this group can contain the element, otherwise false.</returns>
public bool CanContain(string name, SgmlDtd dtd)
{
if (m_declaredContent != DeclaredContent.Default)
return false; // empty or text only node.
return m_model.CanContain(name, dtd);
}
/// <summary>
/// Checks whether an element using this group can contain a specified element.
/// </summary>
/// <param name="name">The name of the element to look for.</param>
/// <param name="dtd">The DTD to use during the checking.</param>
/// <returns>true if an element using this group can contain the element, otherwise false.</returns>
/// <remarks>
/// Rough approximation - this is really assuming an "Or" group
/// </remarks>
public bool CanContain(string name, SgmlDtd dtd)
{
if (dtd == null)
throw new ArgumentNullException("dtd");
// Do a simple search of members.
foreach (object obj in Members)
{
if (obj is string)
{
if (string.Equals((string)obj, name, StringComparison.OrdinalIgnoreCase))
return true;
}
}
// didn't find it, so do a more expensive search over child elements
// that have optional start tags and over child groups.
foreach (object obj in Members)
{
string s = obj as string;
if (s != null)
{
ElementDecl e = dtd.FindElement(s);
if (e != null)
{
if (e.StartTagOptional)
{
// tricky case, the start tag is optional so element may be
// allowed inside this guy!
if (e.CanContain(name, dtd))
return true;
}
}
}
else
{
Group m = (Group)obj;
if (m.CanContain(name, dtd))
return true;
}
}
return false;
}
/// <summary>
/// Tests whether this element can contain another specified element.
/// </summary>
/// <param name="name">The name of the element to check for.</param>
/// <param name="dtd">The DTD to use to do the check.</param>
/// <returns>True if the specified element can be contained by this element.</returns>
public bool CanContain(string name, SgmlDtd dtd)
{
// return true if this element is allowed to contain the given element.
if (m_exclusions != null)
{
foreach (string s in m_exclusions)
{
if (string.Equals(s, name, StringComparison.OrdinalIgnoreCase))
return false;
}
}
if (m_inclusions != null)
{
foreach (string s in m_inclusions)
{
if (string.Equals(s, name, StringComparison.OrdinalIgnoreCase))
return true;
}
}
return m_contentModel.CanContain(name, dtd);
}