Intellisense无法从扩展方法推断类型 [英] Intellisense cannot infer type from extension method

问题描述

下面的示例成功编译.
编译器可以推断e(客户)的类型
我的问题是为什么Intellisense无法做同样的事情?
当我键入 customer.SetValue(时，它正确显示该方法期望

The example below compiles successfully.
The compiler can infer the type of e (Customer)
My question is why Intellisense cannot do the same?
When I type customer.SetValue( it correctly shows that the method expects

 Expression<Func<Customer, TProperty>>

但是当我键入 e => e.时，它无法理解e是客户

but when I type e => e. it cannot understand that e is a Customer

这是预期的还是错误?

using System;
using System.Linq.Expressions;
using System.Reflection;

namespace ConsoleApplicationExpressionTree
{
    class Program
    {
        static void Main(string[] args)
        {
            Customer customer = new Customer();
            customer.SetValue(e => e.Age, 10);
            customer.SetValue(e => e.Name, "TheName");
            //type here
         }
     }

     public static class Extentions
     {
        public static void SetValue<TEntity, TProperty>(this TEntity instance, Expression<Func<TEntity, TProperty>> expression, TProperty newValue)
        {
            if (instance == null)
                throw new ArgumentNullException();

            var memberExpression = (MemberExpression)expression.Body;
            var property = (PropertyInfo)memberExpression.Member;

            property.SetValue(instance, newValue, null);
        }
    } 
    public class Customer
    {
        public string Name { get; set; }
         public int Age { get; set; }
    }
}

我正在使用VS 2015，.NET 4.6.1

I'm using VS 2015 ,.NET 4.6.1

更新
它与Expression<>不相关，方法可以更改为

Update
It is not related to Expression<> ,the method can change to

public static void SetValue<TEntity, TProperty>(this TEntity instance, Func<TEntity, TProperty> expression, TProperty newValue)

更新2
我可以用

Update 2
I can reproduce it with

• VS 2015 Enterprise
• VS 2015社区版

似乎可以使用(尚未测试其他版本)

It seems to be working in (Haven't tested other versions)

• VS 2013 Ultimate
• VS 2013 Premium

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