public override object Evaluate(FunctionArgs args)
{
if (args.Arguments.Length != 0)
{
throw new XPathException("No arguments allowed in position()");
}
var item = args.Context as IXPathItem;
if (item == null)
{
return -1;
}
var parent = item.GetParent();
if (parent == null)
{
return -1;
}
var children = parent.GetChildren().ToArray();
for (var n = 0; n < children.Length; n++)
{
if (children[n] == args.Context)
{
return n + 1;
}
}
return -1;
}
public object EvaluateFunction([NotNull] Function function, [NotNull] [ItemNotNull] Opcode[] arguments, [CanBeNull] object context)
{
var func = XPathService.Functions.FirstOrDefault(f => string.Equals(f.Name, function.Name, StringComparison.OrdinalIgnoreCase));
if (func == null)
{
throw new XPathException("Function not found: " + function.Name);
}
var args = new FunctionArgs(this, arguments, context);
return func.Evaluate(args);
}
public override object Evaluate(FunctionArgs args)
{
if (args.Arguments.Length != 2)
{
throw new XPathException("Too many or to few arguments in EndsWith()");
}
var a0 = args.Arguments[0].Evaluate(args.XPathExpression, args.Context);
var a1 = args.Arguments[1].Evaluate(args.XPathExpression, args.Context);
if (!(a0 is string && a1 is string))
{
throw new XPathException("String expression expected in EndsWith()");
}
return a0.ToString().EndsWith(a1.ToString(), StringComparison.OrdinalIgnoreCase);
}
public override object Evaluate(FunctionArgs args)
{
if (args.Arguments.Length != 2)
{
throw new XPathException("Too many or to few arguments in Contains()");
}
var a0 = args.Arguments[0].Evaluate(args.XPathExpression, args.Context);
var a1 = args.Arguments[1].Evaluate(args.XPathExpression, args.Context);
if (!(a0 is string && a1 is string))
{
throw new XPathException("String expression expected in Contains()");
}
return a0.ToString().IndexOf(a1.ToString(), StringComparison.InvariantCulture) >= 0;
}
public override object Evaluate(FunctionArgs args)
{
if (args.Arguments.Length != 0)
{
throw new XPathException("No arguments allowed in last()");
}
var item = args.Context as IXPathItem;
if (item == null)
{
return -1;
}
var parent = item.GetParent();
if (parent != null)
{
return parent.GetChildren().Count();
}
return -1;
}
public abstract object Evaluate(FunctionArgs args);
