在 VS2015 中从包管理器控制台安装 Entityframework 7 时出现 Nuget 错误“对象引用未设置为对象的实例”

Question

I am trying to build a sample application using EF7 and mvc 6 in visual studio 2015 pre release.

While installing both EF7 and MVC6 using package manager console getting this error.

 PM> Install-Package EntityFramework.Commands -Version 7.0.0-beta3 -Pre
 Attempting to gather dependencies information for package    
 'EntityFramework.Commands.7.0.0-beta3' with respect to project
 targeting '.NETFramework, Version=v4.5.3' Install-Package : Object
 reference not set to an instance of an object. At line:1 char:1
 + Install-Package EntityFramework.Commands -Version 7.0.0-beta3 -Pre
 + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     + CategoryInfo          : NotSpecified: (:) [Install-Package], Exception
     + FullyQualifiedErrorId : NuGetCmdletUnhandledException,NuGet.PackageManagement.PowerShellCmdlets.InstallPackageCommand

Can any one help me how to resolve this issue, or I am doing right?

Answer 1

I have solved this problem, by disabling the " https://api.nuget.org/v3/ " from the package source, in order to do this, Choose Tools > Nuget Package Manager > Package Source

And other thing I did is added myget package source " https://www.myget.org/F/aspnetvnext/api/v2/ "

Following the steps Choose Tools > Nuget Package Manager > Package Source > Click add on top of the window and add the myget package source.

Answer 2

I had a similar issue in Visual Studio 2015 Community Edition.

Created a simple ASP.NET MVC 5 default project that I hosted on Azure. I was working through the project and when I tried to load up the NuGet GUI but kept getting the "Object Reference..." error.

I restarted Visual Studio in Administrator mode (right-clicked Visual Studio and started in Administrator mode) which resolved the problem.

Answer 3

I solved my problem by adding:

https://api.nuget.org/v3/index.json

as a Package Sources feed, as shown on the picture below:

Answer 4

My problem solved by activation Microsoft and .NET source , and use it to get package.

Answer 5

What I had is that I was disconnected from the internet while trying to install any package.

Not sure if this covers everyting, but I have to say nuget and the package manager console is a great source for headaches.

Answer 6

In my case, i was having:

Object reference not set to an instance of an object

From package manager and i solved it closing all and opening again.

Answer 7

我认为您的 IP 地址未连接到 nugetpackage 使用代理更改您的 IP 地址 我认为这是真的。

Answer 8

Perfect and ultimate Solution Guys this is the perfect solution for that. First install the latest version of nuget from your visual studio. Then install the sqlite through the last version of nuget you installed already. for more details just look the picture bellow. Thanks] 1 ] 1

Answer 9

我重新启动计算机后，问题就消失了。

Answer 10

对我来说，在解决方案的不同项目中整合 nuget 之后（通过“ Consolidate选项卡），它开始工作。

Answer 11

Perfect and ultimate Solution Guys this is the perfect solution for that. First install the latest version of nuget (Nuget.VisualStudio) from your visual studio. Then install the sqlite through the last version of nuget you installed already. for more details just look the picture bellow. Thanks