blocks|key|455646|text|本质上，问题是匿名类型是作为内部(see+answer)生成的，这使得在视图中不可能对对象的属性进行硬类型引用。本文提供了更详细的解释：|type|unstyled|depth|inlineStyleRanges|entityRanges|offset|length|data|455647|http://www.heartysoft.com/anonymous-types-c-sharp-4-dynamic|455648|可以使用动态匿名包装器类(@Dakill的答案)来完成，但很快就会变得丑陋，应该让程序员问为什么他/她会这样做。|455649|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/5649536/entity-framework-select-new.|1^0|H|A|0|0|0|1N|1|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@$A|R|B|S|1|T]]|C|$]]|$1|D|3|E|5|6|7|U|8|@]|9|@$A|V|B|W|1|X]]|C|$]]|$1|F|3|G|5|6|7|Y|8|@]|9|@]|C|$]]|$1|H|3|-4|5|6|7|Z|8|@]|9|@]|C|$]]]|I|$J|$5|K|L|M|C|$N|O]]|P|$5|K|L|M|C|$N|E]]]]

Essentially the issue is that anonymous types are generated as internal (<a href="https://stackoverflow.com/questions/5649536/entity-framework-select-new.">see answer</a>), making hard typed references to the object's property impossible from the View. This article provides a more detailed explanation: 

<a href="http://www.heartysoft.com/anonymous-types-c-sharp-4-dynamic" rel="nofollow noreferrer">http://www.heartysoft.com/anonymous-types-c-sharp-4-dynamic</a>

It is possible to accomplish with the use of a Dynamic Anonymous wrapper class (@Dakill's answer), but gets ugly fast and should make a programmer question why he/she would do so.

blocks|key|669996|text|与人们普遍认为的相反，这是可以做到的，但涉及到一种丑陋的黑客行为，这将导致未来的维护问题。它涉及到编写一个类来将匿名对象“包装”到一个动态对象中。前段时间我把它当做练习，下面是包装器类的代码，你可以像ViewBag.Stuff+=+new+DynamicAnonymous(new+{+Name+=+"Test",+Email+=+"user@domain.com"+});一样使用它。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|669997|public+class+DynamicAnonymous+:+DynamicObject
{
++++++++++++object+obj;

++++++++++++public+DynamicAnonymous(object+o)
++++++++++++{
++++++++++++++++++++this.obj+=+o;
++++++++++++}

++++++++++++public+override+IEnumerable<string>+GetDynamicMemberNames()
++++++++++++{
++++++++++++++++++++return+obj.GetType().GetProperties().Select(n+=>+n.Name);
++++++++++++}

++++++++++++public+override+bool+TryGetMember(GetMemberBinder+binder,+out+object+result)
++++++++++++{
++++++++++++++++++++var+prop+=+obj.GetType().GetProperty(binder.Name);
++++++++++++++++++++if+(prop+==+null)
++++++++++++++++++++{
++++++++++++++++++++++++++++result+=+null;
++++++++++++++++++++++++++++return+false;
++++++++++++++++++++}
++++++++++++++++++++else
++++++++++++++++++++{
++++++++++++++++++++++++++++result+=+prop.GetValue(obj,+null);
++++++++++++++++++++++++++++return+true;
++++++++++++++++++++}
++++++++++++}

++++++++++++public+override+int+GetHashCode()
++++++++++++{
++++++++++++++++++++return+obj.GetHashCode();
++++++++++++}

++++++++++++public+override+string+ToString()
++++++++++++{
++++++++++++++++++++return+obj.ToString();
++++++++++++}

++++++++++++public+override+bool+Equals(object+obj2)
++++++++++++{
++++++++++++++++++++return+obj.Equals(obj2);
++++++++++++}++++++++++++++++
+}|code-block|syntax|javascript|669998|entityMap^0|2S|2F|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@$9|N|A|O|B|C]]|D|@]|E|$]]|$1|F|3|G|5|H|7|P|8|@]|D|@]|E|$I|J]]|$1|K|3|-4|5|6|7|Q|8|@]|D|@]|E|$]]]|L|$]]

Contrary to popular belief, this can be done, but involves a somewhat ugly hack that will lead to maintenance problems down the road.. It involves writing a class to "wrap" your anonymous object into a dynamic object. I've made it as an exercise some time ago, below is the code to the wrapper class, you would use it like <code>ViewBag.Stuff = new DynamicAnonymous(new { Name = "Test", Email = "user@domain.com" });</code>..

<pre><code>public class DynamicAnonymous : DynamicObject
{
 object obj;

 public DynamicAnonymous(object o)
 {
 this.obj = o;
 }

 public override IEnumerable&lt;string&gt; GetDynamicMemberNames()
 {
 return obj.GetType().GetProperties().Select(n =&gt; n.Name);
 }

 public override bool TryGetMember(GetMemberBinder binder, out object result)
 {
 var prop = obj.GetType().GetProperty(binder.Name);
 if (prop == null)
 {
 result = null;
 return false;
 }
 else
 {
 result = prop.GetValue(obj, null);
 return true;
 }
 }

 public override int GetHashCode()
 {
 return obj.GetHashCode();
 }

 public override string ToString()
 {
 return obj.ToString();
 }

 public override bool Equals(object obj2)
 {
 return obj.Equals(obj2);
 } 
 }
</code></pre>

blocks|key|455831|text|您可以使用NothingsImpossible描述的机制来实现，但不需要使用ExpandoObject实现您自己的包装器。下面是一个示例：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|455832|var+items+=+_repository.GetItems()
++++.Select(og+=>+{
++++++++dynamic+eo+=+new+System.Dynamic.ExpandoObject();
++++++++eo.Id+=+item.Id;
++++++++eo.FriendlyName+=+og.FriendlyName;
++++++++eo.Selected+=+itemIds.Contains(item.Id);
++++++++return+eo;
++++})
++++.ToArray();
ViewBag.Items+=+items;|code-block|syntax|javascript|455833|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You can do it using the mechanism NothingsImpossible descibed, but withou implementing your own wrapper using ExpandoObject. Here is an Example:

<pre><code>var items = _repository.GetItems()
 .Select(og =&gt; {
 dynamic eo = new System.Dynamic.ExpandoObject();
 eo.Id = item.Id;
 eo.FriendlyName = og.FriendlyName;
 eo.Selected = itemIds.Contains(item.Id);
 return eo;
 })
 .ToArray();
ViewBag.Items = items;
</code></pre>

This is probably a silly question, but I am trying to stuff an anonymous object in <code>ViewBag</code> like so: 

<pre><code>ViewBag.Stuff = new { Name = "Test", Email = "user@domain.com" };
</code></pre>

and access it from a View like so:

 @ViewBag.Stuff.Name

I understand ViewBag is dynamic and that "Stuff" is an anonymous object... but when I look with the debugger from the View line above, I can see all the properties with the proper values. Why does the model binder have such a hard time with this?

Is there a good way to accomplish this without creating a model class? I want to continue using <code>new {}</code>

Storing an Anonymous Object in ViewBag

调试器

这可能是一个愚蠢的问题，但我正在尝试在ViewBag中填充一个匿名对象，如下所示：ViewBag.Stuff = new { Name = "Test", Email = "user@domain.com" };并从视图访问它，如下所示：@ViewBag.Stuff.Name我知道ViewBag是动态的，“东西”是一个...

问在ViewBag中存储匿名对象
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