未使用（和引用）的程序集上的程序集引用错误，为什么会出现此错误？

Question

In my solution I have three projects (Web, Business and Data) all are targeting .net 4.5.1. Web references Business and Business references Data.

I need to execute a intitialization method in those three projects depending on the application start. So I have created a Boot class in all projects.

The Boot class in Business inherit from Boot class in Data and Boot class in Web inherite from Boot class in Business

So I have this code :

In Data project :

namespace Data
{
    public class Boot
    {
        public Boot() 
        {
            // init execution
        }
    }
}

In Business project :

namespace Business
{
    public class Boot : Data.Boot
    {
        public Boot() : base()
        {
            // init execution
        }
    }
}

In Web project :

namespace Web
{
    public class Boot : Business.Boot
    {
        public Boot() : base()
        {
            // init execution
        }
    }
}

And when I compile I have an error on my Boot class in Web project :

The type 'Data.Boot' is defined in an assembly that is not referenced. You must add a reference to assembly 'Data, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null'

And I don't understand why my Web project needs to references my Data project.. It never use Data.Boot directly..

Answer 1

You have to add a reference to your data project from within your web and business project. In your case, your web layer is dependent on the business layer and data layer.

To summarize:

• Web project references business project and data project
• business references data project

Answer 2

您必须检查在业务项目中是否引用了数据DLL，如果是，则必须清理解决方案并重新生成它