更新c#中的列表

Question

我有一个存储库类,其中包含一个列表,其中包含在我的网站上填写表单的人,如果他们将参加我的聚会.我使用GetAllRespones读取值,并使用AddResponse(通过接口)向列表中添加值

现在我想检查某人是否已填写我的表单,如果是,我想检查WillAttend的值是否已更改并更新它.

我可以在这下面看到我做了什么

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using PartyInvites.Abstract;

namespace PartyInvites.Models
{
public class GuestResponseRepository : IRepository

{
    private static List<GuestResponse> responses = new List<GuestResponse>();

    IEnumerable<GuestResponse> IRepository.GetAllResponses()
    {
        return responses;
    }

    bool IRepository.AddResponse(GuestResponse response)
    {
       bool exists = responses.Any(x => x.Email == response.Email);
        bool existsWillAttend = responses.Any(x => x.WillAttend == response.WillAttend);

        if (exists == true)
        {
            if (existsWillAttend == true)
            {
                return false;
            }

           var attend =  responses.Any(x => x.Email == response.Email && x.WillAttend == response.WillAttend);
           attend.WillAttend = response.WillAttend;
           return true;

        }

        responses.Add(response);
        return true;
    }
}
}

问题是,我在"attend.WillAttend"收到错误消息

错误是:bool不包含WillAttend的定义,并且没有扩展方法'WillAttend'接受类型bool的第一个参数可以找到

任何人都可以帮我解决我的代码吗？:)

Answer 1

问题出在这里:

var attend = 
        responses.Any(x => x.Email == response.Email && x.WillAttend == response.WillAttend);

Any<>()回报bool.bool没有财产WillAttend.如果你想获得与第一反应x => x.Email == response.Email && x.WillAttend == response.WillAttend使用First()(或FirstOrDefault()不过你的情况,你总是会至少有一个元素,所以只需使用First()):

var attend = responses.First(x => x.Email == response.Email && x.WillAttend != response.WillAttend);
attend.WillAttend = response.WillAttend;

如果您想要使用指定条件的许多响应Where():

var attend = responses.Where(x => x.Email == response.Email && x.WillAttend != response.WillAttend);

if (attend.Any())
{
    //do something
}

此外,您可以使您的方法更简单:

bool IRepository.AddResponse(GuestResponse response)
{
    if (responses.Any(x => x.Email == response.Email)) //here
    {
        if (responses.Any(x => x.WillAttend != response.WillAttend)) //here
        {
            return false;
        }

        var attend = responses.First(x => x.Email == response.Email && x.WillAttend != response.WillAttend);
        attend.WillAttend = response.WillAttend;          
        return true;
    }

    responses.Add(response);
    return true;
}