/// <summary>
/// 转换为可枚举集合
/// </summary>
/// <typeparam name="T">数据类型</typeparam>
/// <param name="root">根</param>
/// <param name="childSelector">下层数据选择器</param>
/// <param name="predicate">子孙筛选条件</param>
/// <param name="enumerateType">枚举方式</param>
/// <returns>已枚举的集合</returns>
public static IEnumerable <IHierarchical <T> > AsEnumerable <T>(this IHierarchical <T> root,
Func <IHierarchical <T>, IEnumerable <IHierarchical <T> > > childSelector, Func <IHierarchical <T>, bool> predicate,
EnumerateType enumerateType = EnumerateType.DfsDlr)
{
yield return(root);
switch (enumerateType)
{
case EnumerateType.DfsDlr:
foreach (var descendant in GetDescendantDfsDlr(root, childSelector, predicate))
{
yield return(descendant);
}
break;
case EnumerateType.Bfs:
foreach (var descendant in GetDescendantsBfs(root, childSelector, predicate))
{
yield return(descendant);
}
break;
}
}
/// <summary>
/// 转换为可枚举集合
/// </summary>
/// <typeparam name="T">实体类型</typeparam>
/// <param name="root">根</param>
/// <param name="enumerateType">枚举方式</param>
/// <returns>已枚举的集合</returns>
public static IEnumerable <T> AsEnumerable <T>(this ITree <T> root,
EnumerateType enumerateType = EnumerateType.DfsDlr)
where T : ITree <T>
{
foreach (var item in root.AsHierarchical().AsEnumerable(enumerateType))
{
yield return((T)item.Current);
}
}
/// <summary>
/// 转换为可枚举集合
/// </summary>
/// <typeparam name="T">数据类型</typeparam>
/// <param name="root">根</param>
/// <param name="predicate">子孙筛选条件</param>
/// <param name="enumerateType">枚举方式</param>
/// <returns>已枚举的集合</returns>
public static IEnumerable <IHierarchical <T> > AsEnumerable <T>(this IHierarchical <T> root,
EnumerateType enumerateType = EnumerateType.DfsDlr,
Func <IHierarchical <T>, bool> predicate = null)
{
switch (enumerateType)
{
case EnumerateType.DfsDlr:
yield return(root);
foreach (var descendant in GetDescendantsDfsDlr(root, predicate))
{
yield return(descendant);
}
break;
case EnumerateType.DfsLrd:
foreach (var descendant in GetDescendantsDfsLrd(root, predicate))
{
yield return(descendant);
}
yield return(root);
break;
case EnumerateType.Bfs:
yield return(root);
foreach (var descendant in GetDescendantsBfs(root, predicate))
{
yield return(descendant);
}
break;
default:
throw new ArgumentOutOfRangeException(nameof(enumerateType), enumerateType, null);
}
}
private static ScriptValue CreateArrayIterator([NotNull] Agent agent, [NotNull] ScriptObject array, EnumerateType kind)
{
//https://tc39.github.io/ecma262/#sec-createarrayiterator
var iterator = agent.ObjectCreate(agent.Realm.ArrayIteratorPrototype, SpecialObjectType.ArrayIterator);
iterator.IteratedObject = array;
iterator.ArrayIteratorNextIndex = 0;
iterator.ArrayIterationKind = kind;
return(iterator);
}
private static IEnumerable <ScriptValue> EnumerableOwnProperties([NotNull] Agent agent, [NotNull] ScriptObject obj, EnumerateType type)
{
//https://tc39.github.io/ecma262/#sec-enumerableownproperties
var ownKeys = obj.OwnPropertyKeys();
var properties = new List <ScriptValue>();
foreach (var key in ownKeys)
{
if (key.IsString)
{
var descriptor = obj.GetOwnProperty(key);
if (descriptor != null && descriptor.Enumerable)
{
switch (type)
{
case EnumerateType.Key:
properties.Add(key);
break;
case EnumerateType.Value:
properties.Add(obj.Get(key));
break;
case EnumerateType.KeyValue:
properties.Add(ArrayIntrinsics.CreateArrayFromList(agent, new[] { key, obj.Get(key) }));
break;
default:
throw new ArgumentOutOfRangeException(nameof(type), type, null);
}
}
}
}
return(properties);
}
