无法将类型“string”隐式转换为“XXX.ClassName”
我创建了一个名为 Student 的类，Program.cs 中有以下代码：
public static IList<Student> Students { get; private set; }
private static void AddStudent()
{
/*try
{
Console.Write("First name: ");
//Students.FirstName = Console.ReadLine();
string firstName = Console.ReadLine();
}
catch (ArgumentNullException)
{
Console.WriteLine("Name was left empty.");
}*/
Console.Write("First name: ");
string firstName = Console.ReadLine();
Console.Write("Last name: ");
string lastName = Console.ReadLine();
var newStudent = new Student {FirstName = firstName, LastName = lastName}; //if I use try-catch block, it says: The name 'firstName' doesn't exist in the current context
Students.Add(newStudent);
Console.WriteLine("The new student is added. \nEnter any key to return to main screen.");
Console.ReadKey();
}
public static void SortStudents(IList<Student> students)
{
string temp;
for (int i = 0; i < students.Count; i++)
{
for (int j = 0; j < students.Count; j++)
{
if (string.Compare(students[i].ToString(), students[j].ToString()) < 0)
{
//swap
temp = students[i].ToString();
students[i] = students[j];
students[j] = temp; //error here
}
}
}
Console.WriteLine(students);
}
学生班：
public class Student
{
public string FirstName { get; set; }
public string LastName { get; set; }
public int Age { get; set; }
public string StudentNumber { get; set; }
public string Gender { get; set; }
public string FieldOfStudy { get; set; }
}
我正在尝试实现一种算法，该算法将按字母顺序对输入的名称进行排序，但它会在那里抛出错误。我该如何解决？我也在尝试使用 try-catch 块，但它抛出了我在代码中评论过的错误。提前致谢！
白衣非少年2回答
-
忽然笑
正如一些评论员指出的那样，您可能需要访问Student和比较它们的属性，然后交换对象。所以像这样：public static void SortStudents(IList<Student> students) { //We change this to Type Student, not string. Student temp; for (int i = 0; i < students.Count; i++) { for (int j = 0; j < students.Count; j++) { //We look at the Properties of the object, not the Object.ToString() if (string.Compare(students[i].FirstName, students[j].FirstName) < 0) { //Here we are swapping the objects, because we have determined //Their first names aren't in alphabetical order. temp = students[i]; students[i] = students[j]; students[j] = temp; } } } //For loop, or Foreach loop here to iterate through your collection (ILIST) } -
收到一只叮咚
是否有某种原因导致Student该类无法通过实现IComparable接口来实现这种“排序”逻辑？使用 aList<Student>来保存Student对象将使用此CompareTo方法对对象进行“排序”。这将允许类以任何你想要的方式“排序”。在这种情况下，它按姓氏然后按名字排序。你试过这样做吗？它可能看起来像下面...public class Student : IComparable { public string FirstName { get; set; } public string LastName { get; set; } public int Age { get; set; } public string StudentNumber { get; set; } public string Gender { get; set; } public string FieldOfStudy { get; set; } public int CompareTo(object obj) { Student that = (Student)obj; if (this.LastName.Equals(that.LastName)) return this.FirstName.CompareTo(that.FirstName); return this.LastName.CompareTo(that.LastName); }}然后，“排序” aList<Student>将只是......Students.Sort();
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相关分类
C#