asp.net C#中的非重复随机数

Question

我在6个asp.net面板服务器控件中有6个问题,我需要以随机顺序逐个显示所有面板(一个问题是可见的,每次都是不可见的).

我不知道如何排除再次生成的数字.我这样写:

    protected void Page_Load(object sender, EventArgs e)
        {
            if (!IsPostBack)
            {
                Random rnd = new Random();
                int startNumber = rnd.Next(1, 6);
                ShowNextPanel(startNumber);
            }
        }

    private void ShowNextPanel(int excludeNumber)
    {
        Random rnd = new Random();
        //I need to exclude the "excludeNumber" here but I don't know how !?
        int number = rnd.Next(1, 6);
        switch (number)
        {
            case 1:
                {
                    Panel1.Visible = true;
                    break;
                }
            case 2:
                {
                    Panel2.Visible = true;
                    break;
                }
            case 3:
                {
                    Panel3.Visible = true;
                    break;
                }
            case 4:
                {
                    Panel4.Visible = true;
                    break;
                }
            case 5:
                {
                    Panel5.Visible = true;
                    break;
                }
            case 6:
                {
                    Panel6.Visible = true;
                    break;
                }
        }

    }
    protected void Button1_Click(object sender, EventArgs e)
    {
       // InsertToDB(1, DropDownList1.SelectedValue);
        Panel1.Visible = false;
        ShowNextPanel(1);

    }
    protected void Button2_Click(object sender, EventArgs e)
    {
       // InsertToDB(2, DropDownList2.SelectedValue);
        Panel2.Visible = false;
        ShowNextPanel(2);

    }
//and go on till button6_click

Answer 1

您可以将数字放在列表中,并根据实数生成随机数,但不会生成列表中的其余项目.

Random random = new Random();
List<int> nums = new {1, 2, 3, 4, 5, 6}; // or whatever you need to put there.
List<int> result = new List<int>(); // will hold your results in order.
while(nums.Count > 0){
    int idx = random.next(0, nums.Count);
    result.add(nums[idx]);
    nums.RemoveAt(idx);
}
return result;

您不必int在nums列表中使用值; 它可以是你的Question对象,或者你需要的任何东西; 你会得到的是随机顺序的项目.