public static object Evaluate([NotNull] this Query query, [NotNull] Opcode opcode, [NotNull] QueryContext contextNode)
{
Assert.ArgumentNotNull(query, nameof(query));
Assert.ArgumentNotNull(opcode, nameof(opcode));
Assert.ArgumentNotNull(contextNode, nameof(contextNode));
var item = contextNode.GetQueryContextItem();
if (item == null)
{
return(opcode.Evaluate(query, contextNode));
}
var queryTranslator = GetQueryTranslator(contextNode);
if (queryTranslator == null)
{
return(opcode.Evaluate(query, contextNode));
}
IDList idList;
try
{
idList = queryTranslator.QueryFast(item.Database, opcode);
}
catch
{
idList = null;
}
if (idList == null)
{
return(opcode.Evaluate(query, contextNode));
}
if (idList.Count == 1)
{
return(new QueryContext(item.Database.DataManager, idList[0]));
}
var result = new List <QueryContext>();
foreach (ID id in idList)
{
result.Add(new QueryContext(item.Database.DataManager, id));
}
return(result.ToArray());
}
public static string GetString([NotNull] this Query query, [NotNull] QueryContext contextNode, [NotNull] Opcode expression)
{
Assert.ArgumentNotNull(query, nameof(query));
Assert.ArgumentNotNull(contextNode, nameof(contextNode));
Assert.ArgumentNotNull(expression, nameof(expression));
return(expression.Evaluate(query, contextNode) as string);
}
public static Item GetItem([NotNull] this Query query, [NotNull] QueryContext contextNode, [NotNull] Opcode expression)
{
Assert.ArgumentNotNull(query, nameof(query));
Assert.ArgumentNotNull(contextNode, nameof(contextNode));
Assert.ArgumentNotNull(expression, nameof(expression));
var result = expression.Evaluate(query, contextNode);
var instance = result as QueryContext;
if (instance == null)
{
return(null);
}
return(instance.GetQueryContextItem());
}