/// <summary>
/// 通过页索引进行分页。
/// </summary>
/// <param name="index">给定的页索引。</param>
/// <param name="size">给定的页大小。</param>
/// <returns>返回 <see cref="PagingInfo"/>。</returns>
public PagingInfo PageByIndex(int index, int size)
{
_info.ComputeByIndex(index, size);
PageCore();
return(_info);
}