c#怎麽在不同數字區間產生隨機數

int[] all = new int[] { 1,2,4,7,8,9 };

for (int h = 0, j = 0, k = 0; h < ra.Length; h++)

{

System.Random rand = new Random(DateTime.Now.Millisecond);

j = rand.Next(h, all.Length);

k = all[j];

all[j] = all[h];

all[h] = k;

}

//然後取這個被隨機打亂的數組中的第壹位或最後壹位，把剩下的做成下壹個數組，繼續打亂，繼續選取即可