缺少编译器要求会员'System.Runtime.CompilerServices.ExtensionAttribute..ctor“

本文介绍了缺少编译器要求会员'System.Runtime.CompilerServices.ExtensionAttribute..ctor“的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我有针对性地.NET 4.0的项目。它用来建立，直到昨天。我看着代码和引用的程序。我可以看到所定义的扩展属性。 。任何人有任何关于它的线索

I have a project targeted to .Net 4.0. It used to build till yesterday. I looked at code and referenced assemblies. I can see the Extension attribute defined. Anyone has any clue about it.

我提到以下几个问题，但没有任何帮助 - 的"缺少编译器要求会员"而几乎没有改变代码抛出错误多次

I referred following questions but no help - "Missing compiler required member" error being thrown multiple times with almost no changes to code

*更新1：* 我看到Npgsql在相同的命名空间定义ExtensionAttribute。当我删除，并添加Npgsql的旧版本，它内置。我应该怎么做才能使用最新的Npgsql？

* UPDATE 1: * I see Npgsql is defining ExtensionAttribute in the same namespace. When I removed and added older version of Npgsql, it built. What should I do to use latest Npgsql?

推荐答案

这发生在我最近，我的研究一直回来与JSON.Net不是针对存在的问题正确的版本。

This happened to me recently, and my research kept coming back to problems with JSON.Net not targeting the correct version.

如果您正在使用它，我建议从你引用删除它，和删除您packages.config行也引用它。然后通过的NuGet重新安装和编译。

If you are using it, I would suggest removing it from your references, and removing the lines from your packages.config that also reference it. Then re-install it through NuGet and compile.