Could not load file or assembly 'Newtonsoft.Json, Version=3.5.0.0, Culture=neutral, PublicKeyToken=b9a188c8922137c6' or one of its dependencies. The located assembly's manifest definition does not match the assembly reference. (Exception from HRESULT: 0x80131040)
http://stackoverflow.com/questions/3374279/help-me-for-json-unknown-problem
That assembly either needs to be placed in your applications root directory or in your GAC.
ExtAspNet依赖于Newtonsoft.Json.dll
ExtAspNet.dll只有一个For Net2.0的版本，无论你的项目是2.0、3.5、4.0，都只需要引用同一个ExtAspNet.dll即可。
而Newtonsoft.Json.dll为在每个DotNet下都有自己的版本，比如你的项目是基于.Net 2.0的，就要引用json.net\Net20\Newtonsoft.Json.dll，如果你的项目是基于.Net 4.0的，就要引用json.net\Net40\Newtonsoft.Json.dl
程序集需要放到项目根目录下面 如图：
