Microsoft.CSharp.RuntimeBinder.RuntimeBinderException “object”未包含”xx”的定义

问题：无法访问对象的某个属性

原因1：对象被cast成object，所以当然找不到对应的属性。这类问题多出在asp.net mvc 动态属性上，比如：

ViewBag.UserName = new { FirstName = “james”, MiddleName = “T”, LastName = “K” };

前端mvc直接调用@ViewBag.UserName.FirstName

提示如标题的异常提示。

解决办法：新增个扩展方法

public static ExpandoObject ToExpando(this object anonymousObject){IDictionary<string, object> anonymousDictionary = new RouteValueDictionary(anonymousObject);IDictionary<string, object> expando = new ExpandoObject();foreach (var item in anonymousDictionary)expando.Add(item);return (ExpandoObject)expando;}

然后把控制器代码改为

ViewBag.UserName = new { FirstName = “james”, MiddleName = “T”, LastName = “K” }.ToExpando();

前端调用@ViewBag.UserName .FirstName即可正常显示了。

原因2：对象的属性是Internal的，无法跨Assembly访问，解决办法，设置InternalsVisibleTo.

当前程序集的AssemblyInfo.cs中加上

[assembly: InternalsVisibleTo("ClassLibrary1")]

指定对指定程序集可见即可。