internal object Resolve(string pathText = null, ObtainMode obtainMode = ObtainMode.Auto, Type targetType = null)
{
var node = this;
Reflection.Expressions.IMemberExpression accessor = null;
if (!string.IsNullOrWhiteSpace(pathText))
{
var expression = Collections.HierarchicalExpression.Parse(pathText);
node = this.Find(expression.Path) ??
throw new PluginException($"Not found the PluginTreeNode with '{expression.Path}' path.");
accessor = expression.Accessor;
}
//获取指定路径的目标对象
object target = node.UnwrapValue(obtainMode, targetType == null ? null : new Builders.BuilderSettings(targetType));
if (target != null && accessor != null)
{
return(Reflection.Expressions.MemberExpressionEvaluator.Default.GetValue(accessor, target));
}
return(target);
}
public static HierarchicalExpression Parse(string text, int start, int count, Action <string> onError)
{
if (string.IsNullOrEmpty(text))
{
return(null);
}
if (start < 0 || start >= text.Length)
{
throw new ArgumentOutOfRangeException(nameof(start));
}
if (count < 1)
{
count = text.Length - start;
}
else if (count > text.Length - start)
{
throw new ArgumentOutOfRangeException(nameof(count));
}
//创建解析上下文对象
var context = new StateContext(text.AsSpan(start, count));
Reflection.Expressions.IMemberExpression accessor = null;
IList <string> segments = null;
//状态迁移驱动
for (int i = start; i < start + count; i++)
{
if (context.State == State.Exit)
{
var index = context.Character == '@' ? i : i - 1;
if ((accessor = Reflection.Expressions.MemberExpressionParser.Parse(text, index, -1, onError)) == null)
{
return(null);
}
else
{
break;
}
}
if (!context.Read())
{
continue;
}
switch (context.State)
{
case State.None:
if (!DoNone(ref context, i, onError))
{
return(null);
}
break;
case State.Slash:
if (!DoSlash(ref context, i, onError))
{
return(null);
}
break;
case State.AnchorCurrent:
if (!DoAnchorCurrent(ref context, i, onError))
{
return(null);
}
break;
case State.AnchorParent:
if (!DoAnchorParent(ref context, i, onError))
{
return(null);
}
break;
case State.Segment:
if (!DoSegement(ref context, i, segment =>
{
if (segments == null)
{
segments = new List <string>();
}
segments.Add(segment);
}, onError))
{
return(null);
}
break;
}
}
if (context.State == State.Segment)
{
//获取最终的解析结果
var segment = context.Accept(0);
if (segment != null && segment.Length > 0)
{
if (segments == null)
{
segments = new string[] { segment }
}
;
else
{
segments.Add(segment);
}
}
}
return(new HierarchicalExpression(context.Anchor, segments?.ToArray(), accessor));
}
