/// <summary>
/// 从指定的多个值中，随机挑选一个返回。
/// </summary>
/// <typeparam name="T">要随机挑选的值的类型。</typeparam>
/// <param name="items">要随机挑选的值。</param>
/// <returns>随机挑选的值。</returns>
/// <exception cref="ArgumentNullException"><paramref name="items"/> 为 <c>null</c>。</exception>
/// <exception cref="ArgumentException"><paramref name="items"/> 为空数组。</exception>
public static T Choose <T>(params T[] items)
{
CommonExceptions.CheckCollectionEmpty(items, nameof(items));
Contract.EndContractBlock();
if (items.Length == 1)
{
return(items[0]);
}
var index = Random.Next(items.Length);
return(items[index]);
}