对于接口的可选参数 [英] Optional parameters for interfaces

问题描述

使用C＃4.0 - 建立一个接口和实现接口的类。我要声明的接口的可选参数，并将它在课堂上得到体现。所以，我有以下几点：

Using c# 4.0 -- building an interface and a class that implements the interface. I want to declare an optional parameter in the interface and have it be reflected in the class. So, I have the following:

 public interface IFoo
 {
      void Bar(int i, int j=0);
 }

 public class Foo
 {
      void Bar(int i, int j=0) { // do stuff }
 }

这编译，但它看起来不正确。接口需要有可选参数，否则它不会正确的接口方法签名反映。

This compiles, but it doesn't look right. The interface needs to have the optional parameters, because otherwise it doesn't reflect correctly in the interface method signature.

我应该跳过可选参数，只使用可空类型？ ？还是将这项工作作为目的，没有副作用或后果

Should I skip the optional parameter and just use a nullable type? Or will this work as intended with no side effects or consequences?

推荐答案

您可以考虑预先可选参数的选择：

You could consider the pre-optional-parameters alternative:

public interface IFoo
{
    void Bar(int i, int j);
}

public static class FooOptionalExtensions
{
    public static void Bar(this IFoo foo, int i)
    {
        foo.Bar(i, 0);
    }
}

如果你不喜欢新的外观语言功能，你不必使用它。

If you don't like the look of a new language feature, you don't have to use it.

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