把这个50个数的顺序打乱，分别显示出来？？怎么做？？？

public void RandSort(int[] _num)
{
Random rd = new Random();
int temp = 0, tempNum = 0;
for (int i = 0; i < _num.Length-1; i++)
{
temp = rd.Next(i, _num.Length);
tempNum=_num[i];
_num[i] = _num[temp];
_num[temp] = tempNum;
Thread.Sleep(20);//注意：引入命名空间：System.Threading;
}
string str = null;
foreach (int item in _num)
{
str += item.ToString() + ",";
}
MessageBox.Show(str);
}