/// <summary>
/// Constructor
/// </summary>
/// <param name="parent"></param>
public FilterValuePair(FilterGrammarBase parent = null)
: base(FilterGrammar.Value)
{
FilterGrammarBase.SetParent(this, parent);
this.propertyValues = new List<string>();
}
/// <summary>
/// Helper function. 1) Controls what can access setting the parent. 2) avoids null checks everywhere
/// </summary>
/// <param name="node"></param>
/// <param name="parent"></param>
protected static void SetParent(FilterGrammarBase node, FilterGrammarBase parent)
{
if (node == null)
return;
// nothing to do if the parent is already the parent
if (Object.ReferenceEquals(node.Parent, parent))
return;
// make sure the parent node isn't already in the tree
if (FilterGrammarBase.IsAncestor(node, parent))
throw new RecursiveTree("Can not attache parent node, infinite loop detected");
if (FilterGrammarBase.IsAncestor(parent, node))
throw new RecursiveTree("Can not attache parent node, infinite loop detected");
node.Parent = parent;
}
/// <summary>
/// Constructor
/// </summary>
/// <param name="parent"></param>
public FilterNode(FilterGrammarBase parent = null)
: base(FilterGrammar.TreeBranch)
{
FilterGrammarBase.SetParent(this, parent);
SetChild(null);
}
/// <summary>
/// Need a way to check for infinite loops.
/// </summary>
/// <param name="node">Base node</param>
/// <param name="ancestorCheck">Node to search for in relation to the base node</param>
protected static bool IsAncestor(FilterGrammarBase node, FilterGrammarBase ancestorCheck)
{
if (node == null || ancestorCheck == null)
return false;
FilterGrammarBase p = node.Parent as FilterGrammarBase;
while (p != null)
{
if (Object.ReferenceEquals(p, ancestorCheck))
return true;
p = p.Parent;
}
return false;
}
