比较两个庞大(>50.000项)的最快(和最少资源密集型)的方法是什么,从而得到如下所示的两个列表:

在第一个列表中出现但在第二个列表中没有出现的项目 出现在第二个列表中但不在第一个列表中的项目

目前,我正在使用列表或IReadOnlyCollection,并在linq查询中解决这个问题:

var list1 = list.Where(i => !list2.Contains(i)).ToList();
var list2 = list2.Where(i => !list.Contains(i)).ToList();

但这并不像我想的那样好。 有什么想法使这更快和更少的资源密集,因为我需要处理很多列表?


当前回答

我认为这是一个简单易行的方法来逐个元素比较两个列表

x=[1,2,3,5,4,8,7,11,12,45,96,25]
y=[2,4,5,6,8,7,88,9,6,55,44,23]

tmp = []


for i in range(len(x)) and range(len(y)):
    if x[i]>y[i]:
        tmp.append(1)
    else:
        tmp.append(0)
print(tmp)

其他回答

一行:

var list1 = new List<int> { 1, 2, 3 };
var list2 = new List<int> { 1, 2, 3, 4 };
if (list1.Except(list2).Count() + list2.Except(list1).Count() == 0)
    Console.WriteLine("same sets");

不是针对这个问题,但是这里有一些代码来比较相等和不相等的列表!相同的对象:

public class EquatableList<T> : List<T>, IEquatable<EquatableList<T>> where    T : IEquatable<T>

/// <summary>
/// True, if this contains element with equal property-values
/// </summary>
/// <param name="element">element of Type T</param>
/// <returns>True, if this contains element</returns>
public new Boolean Contains(T element)
{
    return this.Any(t => t.Equals(element));
}

/// <summary>
/// True, if list is equal to this
/// </summary>
/// <param name="list">list</param>
/// <returns>True, if instance equals list</returns>
public Boolean Equals(EquatableList<T> list)
{
    if (list == null) return false;
    return this.All(list.Contains) && list.All(this.Contains);
}

我认为这是一个简单易行的方法来逐个元素比较两个列表

x=[1,2,3,5,4,8,7,11,12,45,96,25]
y=[2,4,5,6,8,7,88,9,6,55,44,23]

tmp = []


for i in range(len(x)) and range(len(y)):
    if x[i]>y[i]:
        tmp.append(1)
    else:
        tmp.append(0)
print(tmp)

我做了比较两个列表的泛型函数。

 public static class ListTools
{
    public enum RecordUpdateStatus
    {
        Added = 1,
        Updated = 2,
        Deleted = 3
    }


    public class UpdateStatu<T>
    {
        public T CurrentValue { get; set; }
        public RecordUpdateStatus UpdateStatus { get; set; }
    }

    public static List<UpdateStatu<T>> CompareList<T>(List<T> currentList, List<T> inList, string uniqPropertyName)
    {
        var res = new List<UpdateStatu<T>>();

        res.AddRange(inList.Where(a => !currentList.Any(x => x.GetType().GetProperty(uniqPropertyName).GetValue(x)?.ToString().ToLower() == a.GetType().GetProperty(uniqPropertyName).GetValue(a)?.ToString().ToLower()))
            .Select(a => new UpdateStatu<T>
            {
                CurrentValue = a,
                UpdateStatus = RecordUpdateStatus.Added,
            }));

        res.AddRange(currentList.Where(a => !inList.Any(x => x.GetType().GetProperty(uniqPropertyName).GetValue(x)?.ToString().ToLower() == a.GetType().GetProperty(uniqPropertyName).GetValue(a)?.ToString().ToLower()))
            .Select(a => new UpdateStatu<T>
            {
                CurrentValue = a,
                UpdateStatus = RecordUpdateStatus.Deleted,
            }));


        res.AddRange(currentList.Where(a => inList.Any(x => x.GetType().GetProperty(uniqPropertyName).GetValue(x)?.ToString().ToLower() == a.GetType().GetProperty(uniqPropertyName).GetValue(a)?.ToString().ToLower()))
         .Select(a => new UpdateStatu<T>
         {
             CurrentValue = a,
             UpdateStatus = RecordUpdateStatus.Updated,
         }));

        return res;
    }

}

试试这个方法:

var difList = list1.Where(a => !list2.Any(a1 => a1.id == a.id))
            .Union(list2.Where(a => !list1.Any(a1 => a1.id == a.id)));