// Function to execute a specified user-defined XPath extension
// function at run time.
public object Invoke(System.Xml.Xsl.XsltContext xsltContext,
object[] args, System.Xml.XPath.XPathNavigator docContext)
{
if (FunctionName == "CountChar")
{
return((Object)CountChar((XPathNodeIterator)args[0],
Convert.ToChar(args[1])));
}
if (FunctionName == "FindTaskBy")
{
return(FindTaskBy((XPathNodeIterator)args[0],
Convert.ToString(args[1])));
}
if (FunctionName == "Left")
{
return((Object)Left(Convert.ToString(args[0]),
Convert.ToInt16(args[1])));
}
if (FunctionName == "Right")
{
return((Object)Right(Convert.ToString(args[0]),
Convert.ToInt16(args[1])));
}
return(null);
}
internal HtmlNode SelectSingleNode(string xpath, System.Xml.Xsl.XsltContext additionalContext)
{
Debug.Assert(m_XmlNode != null);
Debug.Assert(xpath != null);
if (xpath == null)
{
throw new ArgumentNullException("xpath");
}
//TODO: The XPATH is mixes case because if not some XPath functions will not work
// May be we need an XPathExpression parser, which will only change the
// case of the elements and attribute names !!! Will be very cool.
XmlNode result = m_XmlNode.SelectSingleNode(xpath, XPath.HtmlXsltContext.GetInstance(additionalContext));
if (result == null || (!(result is XmlRefElement) && !(result is XmlRefAttribute)))
{
return(null);
}
else
{
IHtmlNodeReferenceHolder resRef = result as IHtmlNodeReferenceHolder;
if (resRef != null)
{
return(resRef.HtmlNodeReference);
}
Debug.Assert(false);
throw new XPathException("The type returned by an XPath operation was unexpected!");
}
}
/// <summary>
/// Selects the list of nodes matching the XPath expression. External user-defined functions will be resolved using the supplied System.Xml.Xsl.XsltContext.
/// </summary>
/// <param name="xpath">The XPath expression.</param>
/// <param name="additionalContext">An System.Xml.Xsl.XsltContext to use for resolving any user-defined functions
/// used in the XPath expression.</param>
/// <exception cref="System.Xml.XPath.XPathException"></exception>
/// <exception cref="Acrux.Html.HtmlParserException"></exception>
/// <returns>An Acrux.Html.HtmlNodeList containing a collection of nodes matching the XPath
/// query. The HtmlNodeList should not be expected to be connected "live" to the
/// HTML document. That is, changes that appear in the HTML document may not appear
/// in the HtmlNodeList, and vice versa.</returns>
internal HtmlNodeList SelectNodes(string xpath, System.Xml.Xsl.XsltContext additionalContext)
{
Debug.Assert(m_XmlNode != null);
Debug.Assert(xpath != null);
if (xpath == null)
{
throw new ArgumentNullException("xpath");
}
//TODO: The XPATH is mixes case because if not some XPath functions will not work
// May be we need an XPathExpression parser, which will only change the
// case of the elements and attribute names !!! Will be very cool.
try
{
XmlNodeList result = m_XmlNode.SelectNodes(xpath, XPath.HtmlXsltContext.GetInstance(additionalContext));
return(new HtmlNodeList(result));
}
catch (Exception ex)
{
throw new XPathException(string.Format(CultureInfo.InvariantCulture, "Error selecting nodes. X-Path expression: {0}", xpath), ex);
}
}
internal object EvaluateXPath(string xpath, System.Xml.Xsl.XsltContext additionalContext)
{
Debug.Assert(m_XmlNode != null);
Debug.Assert(xpath != null);
if (xpath == null)
{
throw new ArgumentNullException("xpath");
}
//TODO: [MOVE AS A DEVELOPMENT TASK] - Implement XPath Expression Parser
// The XPATH is mixed case because if not some XPath functions will not work
// May be we need an XPathExpression parser, which will only change the
// case of the elements and attribute names !!! Will be very cool.
XPathNavigator nav = m_XmlNode.CreateNavigator();
XPathExpression expr = nav.Compile(xpath);
expr.SetContext(XPath.HtmlXsltContext.GetInstance(additionalContext));
try
{
object result = nav.Evaluate(expr);
return(result);
}
catch (XPathException ex)
{
throw new XPathException(string.Format(CultureInfo.InvariantCulture, "Error evaluating X-Path expression: {0}", xpath), ex);
}
}
// Function to execute a specified user-defined XPath extension
// function at run time.
public object Invoke(System.Xml.Xsl.XsltContext xsltContext,
object[] args, System.Xml.XPath.XPathNavigator docContext)
{
var result = GetMatchingFunction(this.FunctionName, this.GetType(),
(method, xpathExtensionAttr) =>
{
var methodArgs = args
.Zip(method.GetParameters(),
(arg, parameter) => xpathExtensionAttr.BindArgumentToParameter(arg, parameter))
.ToArray();
return(method.Invoke(this, methodArgs));
},
() =>
{
var msgLine1 = $"`{this.GetType().FullName}` does not contain a method" +
$" that implements `{this.FunctionName}` with an Attribute that extends {typeof(IExtendXPath).FullName}";
var msgLine2 = $"\nEnsure there is a single attribute extending {typeof(IExtendXPath).FullName} a method" +
$" named, or with {typeof(IExtendXPath).FullName}.Name equal to `{this.FunctionName}` on {this.GetType().FullName}.";
throw new Exception(msgLine1 + msgLine2);
});
return(result);
}
public XPathMessageFilter(System.Xml.XmlReader reader, System.Xml.Xsl.XsltContext context)
{
}
public XPathMessageFilter(string xpath, System.Xml.Xsl.XsltContext context)
{
}
public XPathMessageQuery(string expression, System.Xml.Xsl.XsltContext context)
{
}