Question

我有以下方法来比较任何给定复杂类型的两个集合。在执行Sequence Equal操作之前，我需要使用要比较的类型的给定属性对两个集合进行排序，以确保对象的顺序相同。

    public static bool CompareCollections<T>(IEnumerable<T> expectedCollection, IEnumerable<T> actualCollection,Func<T,string> selector)
    {
        if (expectedCollection.Count() != actualCollection.Count())
        {
            return false;
        }
        expectedCollection.OrderBy(selector).ToList();
        actualCollection.OrderBy(selector).ToList();
        return expectedCollection.SequenceEqual(actualCollection, new TypeComparer<T>());
    }

我正在调用以下方法

CompareCollections(first,second,x => x.ID)

第一个和第二个集合如下所示，注意两个集合具有相同的两个对象，但第二个集合的项目顺序相反，我希望OrderBy方法在比较之前对其进行排序平等。但它没有像我预期的那样排序

      var first = new List<Fee>()
      {
        new Fee
        {
            ID = "00001",
            BaseFee = "3.50"
        },
        new Fee
        {
            ID = "00002",
            BaseFee = "5.50"
        }
      };

      var second = new List<Fee>()
      {
        new Fee
        {
            ID = "00002",
            BaseFee = "5.50"
        },
        new Fee
        {
            ID = "00001",
            BaseFee = "3.50"
        }
      };

Answer 1

您需要将OrderBy().ToList()的结果分配到新的局部变量中。 OrderBy返回有序序列，它不会对传入的序列进行就地排序。因此：

var sortedExpectedCollection = expectedCollection.OrderBy(selector);
var sortedActualCollection = actualCollection.OrderBy(selector);

return sortedExpectedCollection.SequenceEqual(sortedActualCollection , new TypeComparer<T>());

Answer 2

您可以这样做：

public static bool CompareCollections<T>(IEnumerable<T> expectedCollection, IEnumerable<T> actualCollection,
                                         Func<T, string> selector)
{
    var expectedAsList = expectedCollection.OrderBy(selector).ToList();
    var actualAsList = actualCollection.OrderBy(selector).ToList();

    return expectedAsList.Count == actualAsList.Count &&
           !expectedAsList.Where((t, i) => !t.Equals(actualAsList[i])).Any();
}

Answer 3

expectedCollection = expectedCollection.OrderBy(selector).ToList();
actualCollection = actualCollection.OrderBy(selector).ToList();

如果排序是问题，只需将值分配给列表并进行比较。

使用属性订购两个复杂类型的通用集合

3 个答案: