Error: Cannot convert from method group to string

Question

我正在学习教程并遇到错误：

"cannot convert from 'method group' to 'string'".

我在cs项目中使用的是.net 5.0框架。

下面是代码。错误即将上线：

yield return new Student(_names[index].First, _names[index].Last);

StudentRepository.cs

public record Name(string First, string Last);

public class StudentRepository: IRepository<Student>
{
    private Name[] _names = new Name[10];

    public StudentRepository()
    {
        _names[0] = new("Steve", "Smith");
        _names[1] = new("Chad", "Smith");
        _names[2] = new("Ben", "Smith");
        _names[3] = new("Eric", "Smith");
        _names[4] = new("Julie", "Lerman");
        _names[5] = new("David", "Starr");
        _names[6] = new("Aaron", "Skonnard");
        _names[7] = new("Aaron", "Stewart");
        _names[8] = new("Aaron", "Powell");
        _names[9] = new("Aaron", "Frost");
    }

    public IEnumerable<Student> List()
    {
        int index = 0;
        while (index < _names.Length)
        {
            yield return new Student(_names[index].First, _names[index].Last);
            index++;
        }
    }
}

Student.cs

public class Student: IComparable<Student>
{
    public static int studentCounter = 0;

    public string FirstName { get; set; }
    public string LastName { get; set; }

    public Student(string firstName, string lastName)
    {
        FirstName = firstName;
        LastName = lastName;
        studentCounter++;
    }

    public override string ToString()
    {
        return $"{FirstName} {LastName}";
    }

    public int CompareTo(Student other)
    {
        if (other is null) return 1;

        if (other.LastName == this.LastName)
        {
            return this.FirstName.CompareTo(other.FirstName);
        }
        return this.LastName.CompareTo(other.LastName);
    }
}

Answer 1

我认为编译器可能会将您的 First-属性与 Linq 的 First() 方法混淆。您使用的是 .NET 5 还是 .NET 6 的预览版？

您可以尝试将 First 和 Last 的名称更改为 FirstName 和 LastName 以查看是否与此有关，或者删除文件顶部的 System.Linq using。

Error: Cannot convert from method group to string

Error: Cannot convert from method group to string

c#

c#-record-type