protected void Button1_Click(object sender, EventArgs e)
    {
        for (int i = 1; i <= 10; i++)
        {
            int Roll_Num = new Random().Next(1, 100);
            this.ListBox1.Items.Add(Roll_Num.ToString());
        }     
    }

每次添加进去的是相同的值……
不会是随机函数太水了吧