比较List< string>和List< T> [英] compare List<string> and List<T>

问题描述

我正在使用C#和Framework 4.0.

I'm using C# and framework 4.0.

我有一个字符串类型的列表和另一个T类类型的列表；

I have a list of type string and another list of type class T;

如何比较列表和列表并保存差异?

How can I compare List with a List and save the difference?

private void simpleButton_Compare_Click(object sender, EventArgs e)
{
    try
    {
        bool Is_Egal = true;                 

        int i = 0;
        foreach (string Od_Scan in Ordre_Scan)
        {
            if (!Outils.Get_Ordre_Donne()[i].NoOrdre.Contains(Od_Scan) && !String.IsNullOrWhiteSpace(Od_Scan))
            {
                Is_Egal = false;
                Temp_Od_Scan.Add(Od_Scan);
            }                    
            i++;
        }

        foreach (Pers_Compare Od_Done in Outils.Get_Ordre_Donne())
        {
            if (!Ordre_Scan.Contains(Od_Done.NoOrdre) && !String.IsNullOrWhiteSpace(Od_Done.NoOrdre))
            {
                Is_Egal = false;
                Temp_Od_Donne.Add(Od_Done);
            }
            else
            {
                Temp_Od_Donne_Egal.Add(Od_Done);
            }
        }

        if (Is_Egal)
        { 
            MessageBox.Show("égalité");
        }
        else
        { 
            MessageBox.Show("PAS égalité"); 
        }

     }
     catch (Exception excThrown)
     {
         MessageBox.Show(excThrown.Message);
     }
 }

和数据:

List<string> Ordre_Scan= new List<string> { "azer","qsdf"};

Pers_Compare obj = new Pers_Compare();
obj.Nolv = 1;
obj.Noordre = "qsdf"

Pers_Compare obj2 = new Pers_Compare();
obj2.Nolv = 1;
obj2.Noordre = "wxcv"

List<Pers_Compare> Ordre_Donne = new List<Pers_Compare>();
Ordre_Donne.add(obj);
Ordre_Donne.add(obj2);

我想将数据保存在Ordre_Donne中，而不要保存在Od_Scan中，反之亦然.

And I want to save the data in Ordre_Donne but not in Od_Scan and vice versa.

foreach (string Od_Scan in Temp_Od_Scan)
{
    all item that not found in List A
    -->  wxcv
}

foreach (var Od_Done in Temp_Od_Donne)
{
    all item that not found in List B
    -->   azer
}

推荐答案

给出的答案

The answer given for a slightly different question (comparing a List with another List) seems to me to be a good solution for your issue, they address multiple issues to do with comparisons of lists.

但是，您应该更具体地满足您的要求，即差异"到底是什么，例如{1,1,2}和{1,2}相同吗?

However you should be more specific with your requirements i.e. what exactly is a 'difference', e.g. is {1,1,2} and {1,2} the same?

以下是获得最高票数的答案...(此处包括只是为了避免由于某种原因(根据鲍勃的建议)将其删除)

Here is the answer given the most votes... (included here just encase it gets removed for some reason (as per Bob' suggestion))

" 说明: 我需要检查它们是否具有相同的元素，而不管它们在列表中的位置如何.每个MyType对象可能在列表上出现多次.有内置的功能可以检查吗?如果我保证每个元素在列表中仅出现一次怎么办?

" DESCRIPTION: I need to check that they both have the same elements, regardless of their position within the list. Each MyType object may appear multiple times on a list. Is there a built-in function that checks this? What if I guarantee that each element appears only once in a list?

伙计们感谢您的回答，但是我忘了添加一些内容，两个列表中每个元素的出现次数应该相同.

Guys thanks for the answers but I forgot to add something, the number of occurrences of each element should be the same on both lists.

答案: 如果您希望它们真正相等(即相同的项目，并且每个项目的编号相同)，我认为最简单的解决方案是在比较之前进行排序:

ANSWER: If you want them to be really equal (i.e. the same items and the same number of each item), I think that the simplest solution is to sort before comparing:

Enumerable.SequenceEqual(list1.OrderBy(t => t), list2.OrderBy(t => t))

这是一种性能更好(大约快十倍)的解决方案，只需要IEquatable而不是IComparable:

public static bool ScrambledEquals<T>(IEnumerable<T> list1, IEnumerable<T> list2) {
  var cnt = new Dictionary<T, int>();
  foreach (T s in list1) {
    if (cnt.ContainsKey(s)) {
      cnt[s]++;
    } else {
      cnt.Add(s, 1);
    }
  }
  foreach (T s in list2) {
    if (cnt.ContainsKey(s)) {
      cnt[s]--;
    } else {
      return false;
    }
  }
  return cnt.Values.All(c => c == 0);
}

要处理任何数据类型作为键(例如，Frank Tzanabetis指出的可为空的类型)，您可以制作一个使用"

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