5

我要一个List<Container>地方Container.Active == true,只给我一个containerObject.Items > 2。如何以这种方式过滤子列表?

using System;
using System.Collections.Generic;
using System.Linq;

namespace ConsoleApplication1
{
    internal class Container
    {
        public List<int> Items { get; set; }
        public bool Active { get; set; }

        public Container(bool active, params int[] items)
        {
            Items = items.ToList();
            Active = active;
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            var containers = new List<Container> {new Container(true,1, 2, 3), new Container(false, 1,2,3,4,5,6), new Container(true,1,2,5,6,7,8,9,10)};
            var result = containers.Where(c => c.Active);

            foreach (var container in result)
            {
                foreach (var item in container.Items)
                {
                    Console.WriteLine(item);//I should not print any values less than two here
                }
            }
        }
    }
}

我不应该在注明的地方打印任何小于 2 的值。

4

5 回答 5

9

尝试这个:

var result = from container in containers.Where(c => c.Active)
             from item in container.Items
             where item > 2
             select container;

标准形式:

var standard_result = containers
    .Where(container => container.Active && container.Items.All(i => i > 2))
    .SelectMany(con => con.Items);
于 2013-03-04T20:29:32.243 回答
4

尝试:

var result = containers.Where(c => c.Active && c.Items.Count() > 2);
于 2013-03-04T20:28:35.250 回答
2

您将不得不创建一个新的Container. 除非您想更改现有的(如果您需要,我将添加该代码)

var result = containers.Where(c => c.Active)
    .Select(c=>new Container(c.Active, c.Select(i=>i>2).ToArray()))
    .Select(c=>c.Items.Count > 0);

如果所有项目都被过滤掉,最后一行确保不返回。

于 2013-03-04T20:29:02.467 回答
2

根据您的反馈,我认为您正在寻找这样的查询:

var result = containers
    .Where(c => c.Active)
    .Select(c => new Container(c.Active, c.Items.Where( i => i>2).ToArray()));

它会复制容器,但它会过滤掉不大于 2 的项目

于 2013-03-04T20:33:56.763 回答
2

如果您真的不需要在单个查询中执行此操作:

var result = containers.Where(c => c.Active).ToList();
result.ForEach(c => c.Items.RemoveAll(i => i <= 2));
于 2013-03-04T20:33:58.463 回答