如何创建最多接受 4 个参数的构造函数？

Question

我正在创建一个最多接受 4 个参数的属性。

我这样编码：

internal class BaseAnnotations

{

    public const string GET = "GET";

    public const string POST = "POST";

    public const string PATCH = "PATCH";

    public const string DELETE = "DELETE";

    public class OnlyAttribute : Attribute

    {

        public bool _GET = false;

        public bool _POST = false;

        public bool _PATCH = false;

        public bool _DELETE = false;

        public OnlyAttribute(string arg1)

        {

            SetMethod(arg1);

        }

        public OnlyAttribute(string arg1, string arg2)

        {

            SetMethod(arg1);

            SetMethod(arg2);

        }

        public OnlyAttribute(string arg1, string arg2, string arg3)

        {

            SetMethod(arg1);

            SetMethod(arg2);

            SetMethod(arg3);

        }

        public OnlyAttribute(string arg1, string arg2, string arg3, string arg4)

        {

            SetMethod(arg1);

            SetMethod(arg2);

            SetMethod(arg3);

            SetMethod(arg4);

        }

        public void SetMethod(string arg)

        {

            switch (arg)

            {

                case GET: _GET = true; break;

                case POST: _POST = true; break;

                case PATCH: _PATCH = true; break;

                case DELETE: _DELETE = true; break;

            }

        }

    }

}

我需要像这样使用它：

public class ExampleModel : BaseAnnotations

{

    /// <summary>

    /// Example's Identification 

    /// </summary>

    [Only(GET, DELETE)]

    public long? IdExample { get; set; }

    // ...

有没有办法只在上面的 4 个构造函数中的一个构造函数中进行编码以避免重复？

我在想像 JavaScript 的 spread operator 之类的东西(...args) => args.forEach(arg => setMethod(arg))。

提前致谢。

Answer 1

我建议在这里重新考虑您的设计。考虑：[Flags]public enum AllowedVerbs{&nbsp; &nbsp; None = 0,&nbsp; &nbsp; Get = 1,&nbsp; &nbsp; Post = 2,&nbsp; &nbsp; Patch = 4,&nbsp; &nbsp; Delete = 8}public class OnlyAttribute : Attribute{&nbsp; &nbsp; private readonly AllowedVerbs _verbs;&nbsp; &nbsp; public bool Get => (_verbs & AllowedVerbs.Get) != 0;&nbsp; &nbsp; public bool Post => (_verbs & AllowedVerbs.Post) != 0;&nbsp; &nbsp; public bool Patch => (_verbs & AllowedVerbs.Patch) != 0;&nbsp; &nbsp; public bool Delete => (_verbs & AllowedVerbs.Delete ) != 0;&nbsp; &nbsp; public OnlyAttribute(AllowedVerbs verbs) => _verbs = verbs;}然后调用者可以使用：[Only(AllowedVerbs.Get)]或者[Only(AllowedVerbs.Post | AllowedVerbs.Delete)]

Answer 2

好的答案，但请考虑使用 4 个属性。对于您的示例，这可能有效。public class GetAttribute: Attribute {}public class PostAttribute: Attribute {}public class PatchAttribute: Attribute {}public class DeleteAttribute: Attribute {}[GET] [DELETE]public long? IdExample { get; set; }它简单而直接。当然还有更多属性，但您可能有更多需要它们的实例。每个属性都有一个默认构造函数。每个操作的属性仅存在就足以传达允许的内容。

Answer 3

&nbsp;public OnlyAttribute(params string[] parameters)&nbsp;{&nbsp; &nbsp; &nbsp; &nbsp; if (parameters.Length > 4) throw new ArugumentException(nameof(parameters));&nbsp; &nbsp; &nbsp; &nbsp; foreach (var param in parameters)&nbsp; &nbsp; &nbsp; &nbsp; {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; SetMethod(param);&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp;}