UPDATE

Question

//this class (or interface if you like) is set up as generic...
public abstract class GenericBase<T> 
{
    public T PerformBasicTask(T in) { ... }
}

//... but is intended to be inherited by objects that close the generic...
public class ConcreteForDates:GenericBase<DateTime>
{
    public DateTime PerformSpecificTask(DateTime in) { ... }
}

//... so that consuming code never knows that a generic is involved
var myDateConcrete = new ConcreteForDates(); //look ma, no GTP!
//These two methods look alike, and there is no generic type inference,
//even with PerformBasicTask().
var basicResult = myDateConcrete.PerformBasicTask(DateTime.Now);
var specificResult = myDateConcrete.PerformSpecificTask(DateTime.Today);

//does not compile because T is understood by inheritance to be a DateTime,
//even though PerformBasicTask() s implementation may well handle an int.
var anotherBasicResult = myDateConcrete.PerformBasicTask(1);

我多次看到和使用这种模式,非常有助于在一系列特定类别下提供共同功能。例如,这可以成为主计长/署长的一种模式,其具体针对的是某类域标,该类别是用来控制该类;检索/保存等基本业务可能使用100%的共同功能,但约束性/无约束力可能非常具体。

如果没有将通用声明透露给最终用户,这种通用声明是否有一个名称?

Answer 1

我认为,这并不是“NET”框架中通用型次系统的一种模式,而是其具体特征,在操作时间以特定类型(例如,日期)取代通用参数。关于共同行为的所有其他内容,均称为。

Answer 2

如果说是这样的话,我将把它称作Specifics,我同意Aliostad,因为它是一位反家长。

Answer 3

Generics is used to reuse a conduct that needs to be specified than the打/em> - or at minimum within the restrictions enforced by the where article.

您所见的例子,IMHO,是generics anti-pattern。类型不应存在,或者如果确实存在,只应在限制中加以界定,即:,处。

基本上,期望所有分流执行摘要的通用摘要类别为,不使用通用性。我不能简单地开始使用<代码>Generic<MyType>,即通用名称。

我认为这败坏了。

In this case there is a slight benefit in using a generic abstract class/interface and that is type safety achieve for PerformSpecificTask.

UPDATE

我知道这是一个有争议的问题,我将向左边和右边开枪,但我认为情况确实如此。

A class can happily subclass a generic class and add more functionality. But in this case, it is the extra functionality that defines the identity of that class. When I cannot just say Generic<MyOwnTypeOfVolition> then I have defeated the objective of generics. Sometimes, however, it is not the generics which I am concerned with - it is the interface which seems to be the case here.

UPDATE 2

一个典型的例子是IConvertible in .NET Framework。

You could setup a generic interface/abstract class for it and ask all subclasses to implement it, but the framework makes it an optional case and supports it only for classes implementing the interface.

UPDATE

UPDATE 2

友情链接