new（）在此上下文中的含义是什么

Question

What does new() mean in the following context:

 public interface ISpecification<TEntity>
        where TEntity : class,new()

Answer 1

It is a constraint on the type parameter TEntity that specifies that it must have a public parameterless constructor.

See Constraints on Type Parameters .

Answer 2

It means you can construct the class with a parameterless public constructor. Or, it lets you do var entity= new TEntity(); without the compiler having fits.