83 lines
2.9 KiB
C#
83 lines
2.9 KiB
C#
// Copyright (c) Microsoft Corporation. All rights reserved. See License.txt in the project root for license information.
|
|
|
|
using System.Collections.Generic;
|
|
using System.Diagnostics;
|
|
using System.Dynamic;
|
|
using System.Linq;
|
|
using System.Linq.Expressions;
|
|
using System.Reflection;
|
|
|
|
namespace System.Web.Helpers.Test
|
|
{
|
|
/// <summary>
|
|
/// Dynamic object implementation over a regualar CLR object. Getmember accesses members through reflection.
|
|
/// </summary>
|
|
public class DynamicWrapper : IDynamicMetaObjectProvider
|
|
{
|
|
private object _object;
|
|
|
|
public DynamicWrapper(object obj)
|
|
{
|
|
_object = obj;
|
|
}
|
|
|
|
public DynamicMetaObject GetMetaObject(Expression parameter)
|
|
{
|
|
return new DynamicWrapperMetaObject(parameter, this);
|
|
}
|
|
|
|
private class DynamicWrapperMetaObject : DynamicMetaObject
|
|
{
|
|
public DynamicWrapperMetaObject(Expression expression, object value)
|
|
: base(expression, BindingRestrictions.Empty, value)
|
|
{
|
|
}
|
|
|
|
private object WrappedObject
|
|
{
|
|
get { return ((DynamicWrapper)Value)._object; }
|
|
}
|
|
|
|
private Expression GetDynamicExpression()
|
|
{
|
|
return Expression.Convert(Expression, typeof(DynamicWrapper));
|
|
}
|
|
|
|
private Expression GetWrappedObjectExpression()
|
|
{
|
|
FieldInfo fieldInfo = typeof(DynamicWrapper).GetField("_object", BindingFlags.NonPublic | BindingFlags.Instance);
|
|
Debug.Assert(fieldInfo != null);
|
|
return Expression.Convert(
|
|
Expression.Field(GetDynamicExpression(), fieldInfo),
|
|
WrappedObject.GetType());
|
|
}
|
|
|
|
private Expression GetMemberAccessExpression(string memberName)
|
|
{
|
|
return Expression.Property(
|
|
GetWrappedObjectExpression(),
|
|
memberName);
|
|
}
|
|
|
|
public override DynamicMetaObject BindGetMember(GetMemberBinder binder)
|
|
{
|
|
var binderDefault = binder.FallbackGetMember(this);
|
|
|
|
var expression = Expression.Convert(GetMemberAccessExpression(binder.Name), typeof(object));
|
|
|
|
var dynamicSuggestion = new DynamicMetaObject(expression, BindingRestrictions.GetTypeRestriction(Expression, LimitType)
|
|
.Merge(binderDefault.Restrictions));
|
|
|
|
return binder.FallbackGetMember(this, dynamicSuggestion);
|
|
}
|
|
|
|
public override IEnumerable<string> GetDynamicMemberNames()
|
|
{
|
|
return (from p in WrappedObject.GetType().GetProperties()
|
|
orderby p.Name
|
|
select p.Name).ToArray();
|
|
}
|
|
}
|
|
}
|
|
}
|