public DataTable GetPagedTable(DataTable dt, int PageIndex, int PageSize)//PageIndex表示第幾頁，PageSize表示每頁的記錄數  {   if (PageIndex == 0)    return dt;//0頁代表每頁數據，直接返回   DataTable newdt = dt.Copy();   newdt.Clear();//copy dt的框架   int rowbegin = (PageIndex - 1) * PageSize;   int rowend = PageIndex * PageSize;   if (rowbegin >= dt.Rows.Count)    return newdt;//源數據記錄數小于等于要顯示的記錄，直接返回dt   if (rowend > dt.Rows.Count)    rowend = dt.Rows.Count;   for (int i = rowbegin; i <= rowend - 1; i++)   {    DataRow newdr = newdt.NewRow();    DataRow dr = dt.Rows[i];    foreach (DataColumn column in dt.Columns)    {     newdr[column.ColumnName] = dr[column.ColumnName];    }    newdt.Rows.Add(newdr);   }   return newdt;  }