public static T RandomElement <T>(this IList <T> list)
{
if (list != null)
{
int indx = RandomEx.GetRange(0, list.Count);
if (list.Count > indx)
{
return(list[indx]);
}
}
return(default(T));
}
public static void Shuffle <T>(this IList <T> list)
{
int n = list.Count;
while (n > 1)
{
n--;
int k = RandomEx.GetRange(0, n + 1);
T val = list[k];
list[k] = list[n];
list[n] = val;
}
}
