Fluent Assertions 中的 Satisfy() 不适用于类对象的集合

Question

我有一堂课：

public class TestClass
{
    public int Id { get; set; }
    
    public int CampusId { get; set; }
    
    public int CurrentStudentCount { get; set; }
    
    public int MaxStudentCount { get; set; }
}

以及该类的对象集合：

var collection = new[]
    {
        new TestClass
        {
            Id = 55,
            CampusId = 38,
            CurrentStudentCount = 1,
            MaxStudentCount = 2
        },
        new TestClass
        {
            Id = 127,
            CampusId = 38,
            CurrentStudentCount = 2,
            MaxStudentCount = 2
        },
        new TestClass
        {
            Id = 126,
            CampusId = 38,
            CurrentStudentCount = 2,
            MaxStudentCount = 2
        }
    };

我想断言每个对象的CampusId 等于 38：

collection.Should().Satisfy(i => i.CampusId == 38);

但断言失败并显示以下消息：

预期集合满足所有谓词，但以下元素不匹配任何谓词：

Index: 1, Element: TestClass

{
    CampusId = 38, 
    CurrentStudentCount = 2, 
    Id = 127, 
    MaxStudentCount = 2
}

Index: 2, Element: TestClass

{
    CampusId = 38, 
    CurrentStudentCount = 2, 
    Id = 126, 
    MaxStudentCount = 2
}

Answer 1

Satisfy（和SatisfyRespectively）要求集合中的每个元素都有一个 lambda。你的情况是：

collection.Should().Satisfy(
    i => i.CampusId == 38,
    i => i.CampusId == 38,
    i => i.CampusId == 38
);

另一种选择是使用OnlyContain：

collection.Should().OnlyContain(i => i.CampusId == 38);