c# - 从 M 集合中取出 n 个唯一对象

Question

我想知道如何在 C# 中完成此任务。例如；

I got 10 questions from which 3 is to be displayed to user for them to type the answer. How can i make the program generate 3 questions that are non-repeating(unique) assuming the 10 questions that we are starting with is unique.

我在 asp.net 应用程序中使用逻辑，并且允许在下次刷新页面时显示同一组问题，所以这对我来说没问题。

Answer 1

为您的问题实例使用一个列表，并随机选择一个(按索引)。然后将其从列表中删除并重复。像这样；

    static void Main(string[] args)
    {
        List<string> questions = new List<string>();
        for (int i = 0; i < 10; i++)
            questions.Add("Question " + i);

        Random r = new Random();
        for (int i = 0; i < 3; i++)
        {
            int nextQuestion = r.Next(0, questions.Count);
            Console.WriteLine(questions[nextQuestion]);
            questions.RemoveAt(nextQuestion);
        }
    }