C# 长度为100的int数组 插入1-100的随机数 不能重复

        private int[] GetRandomArray1(int len = 100)        {            int[] arr = new int[len];            for (int i = 0; i < len; i++)            {                arr[i] = i + 1;            }            Random r = new Random();            for (int i = 0; i < len; i++)            {                var nowIndex = r.Next(0, len);                int nowTemp = arr[nowIndex];                arr[nowIndex] = arr[i];                arr[i] = nowTemp;            }            return arr;        }