问题:Code First 启用迁移时找不到上下文DbContext所在的项目. PM> Enable-Migrations No context type was found in the assembly 'Road.Web'. 解决方法:PM> Enable-Migrations -ProjectName Road.Data -StartUpProjectName Road.Web -Verbose PM> Enable-Migrations No context type was
问题 An error occurred while starting the application. ArgumentException: AddDbContext was called with configuration, but the context type 'NewsContext' only declares a parameterless constructor. This means that the configuration passed to AddDbContext
System.ArgumentException HResult=0x80070057 Message=AddDbContext was called with configuration, but the context type 'MyDBContext' only declares a parameterless constructor. This means that the configuration passed to AddDbContext will never be used.
The Neophyte's Guide to Scala Part 12: Type Classes 过去的两周我们讨论了一些使我们保持DRY和灵活性的函数式编程技术,特别是函数组合,partial function的应用,以及currying.接下来,我将会继续讨论如何使你的代码尽可能的灵活. 但是,这次我们将不会讨论怎么使用函数作为一等对象来达到这个目的,而是使用类型系统,这次它不是阻碍着我们,而是使得我们的代码更灵活:你将会学到关于 type classes 的知识. 你可能会觉得这是一