从高速缓存转换为通用列表< T>引发异常 [英] cast from cache to generic list<T> throws an exception

问题描述

在Asp.net应用程序中.我将Linq to Xml结果缓存到Cache对象.当我将缓存对象投射回通用列表时.我收到以下异常.

In Asp.net application. i cache a Linq to Xml result to a Cache object. when i cast the cache object back to generic list. i get the following exception.

 

[A]System.Collections.Generic.List`1[CarRentalAddress] cannot be cast to [B]System.Collections.Generic.List`1

[CarRentalAddress]. Type A originates from 'mscorlib, Version=2.0.0.0, Culture=neutral,

 PublicKeyToken=b77a5c561934e089' in the context 'LoadNeither' at location 

'C:\WINDOWS\assembly\GAC_32\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll'. Type B originates from 'mscorlib,

 Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089' in the context 'LoadNeither' at location

 'C:\WINDOWS\assembly\GAC_32\mscorlib\2.0.0.0__b77a5c561934e089\mscorlib.dll'.

 

我的代码如下.

 

 

if
 (!Page.IsPostBack)
  {

   if
 (Cache["xml"
] == null
)
   {
    DataSet ds = new
 DataSet();
    ds.ReadXml(HttpContext.Current.Server.MapPath("~/CarRentalAddress.xml"
));
    var
 grid = (from
 d in
 ds.Tables[0].AsEnumerable() orderby
 d.Field<string
>("City"
) where
 d.Field<string
>("Enabled"
) == "1"
 select
 new
 CarRentalAddress { City = d.Field<string
>("City"
), HotelName = d.Field<string
>("HotelName"
), Address = d.Field<string
>("Address"
), EmailID1 = d.Field<string
>("EmailID1"
), EmailID2 = d.Field<string
>("EmailID2"
) }).ToList();
    Cache["xml"
] = grid;
    totalrows = grid.Count().ToString();
    grdAddress.DataSource = grid;
    grdAddress.DataBind();
   }
   else

   {
    //Exception is thrown by this line

    var
 grid = (List<CarRentalAddress>)Cache["xml"
];
    totalrows = grid.Count().ToString();
    grdAddress.DataSource = grid;
    grdAddress.DataBind();
   }
  }

推荐答案

确保所有库都是使用正确的配置(任何CPU或x86)构建的.然后，清理您的整体解决方案并重建它，然后重试.

Make sure that all libraries are built using the right configuration (Any CPU or x86). Then, clean your total solution and rebuild it and try again.

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