DataTable两列转换四列

 

Code
有时候为了节省打印纸张,通常要吧结果分栏显示,这就需要把DataTable两列转换为四列

报表分页时 添加组并添加表达式:

=Int((RowNumber(Nothing)-1)/15)//每页显示15条记录

(两外一个表达式意义不是很清楚=Ceiling(RowNumber(Nothing)/20) )

        /// <summary>
        /// 两列转换为四列
        /// </summary>
        /// <param name="pagesize">每页大小</param>
        /// <param name="table"></param>
        /// <returns></returns>
        private DataTable GetStudentRegesterBook(int pagesize,DataTable table)
        {
            
            DataTable dt = new DataTable();
            int rows = table.Rows.Count;
            if (rows > 0)
            {
                dt.Columns.Add("xh1", typeof(string));
                dt.Columns.Add("xm1", typeof(string));
                dt.Columns.Add("xh2", typeof(string));
                dt.Columns.Add("xm2", typeof(string));

                int pagecount = 0;
                pagecount = rows / pagesize;
                if (pagecount * pagesize < rows)
                    pagecount = pagecount + 1;

                int i, j, k;
                //考虑前pagecount-1页
                if (rows > 0)
                {
                    for (i = 0; i < pagecount - 1; i++)
                    {
                        if (i % 2 == 0)
                        {
                            for (j = 0; j < pagesize; j++)
                            {
                                DataRow dr = dt.NewRow();
                                dr["xh1"] = table.Rows[j + i * pagesize]["xh"].ToString();
                                dr["xm1"] = table.Rows[j + i * pagesize]["xm"].ToString();
                                dt.Rows.Add(dr);
                            }
                        }
                        else
                        {
                            for (k = 0; k < pagesize; k++)
                            {

                                dt.Rows[k + (i / 2) * pagesize]["xh2"] = table.Rows[k + i * pagesize]["xh"].ToString();
                                dt.Rows[k + (i / 2) * pagesize]["xm2"] = table.Rows[k + i * pagesize]["xm"].ToString();

                            }
                        }


                    }
                    //考虑最后一页
                    //奇数页
                    if (pagecount % 2 == 1)
                    {

                        for (k = 0; k < rows - (pagecount - 1) * pagesize; k++)
                        {
                            DataRow dr = dt.NewRow();
                            dr["xh1"] = table.Rows[k + i * pagesize]["xh"].ToString();
                            dr["xm1"] = table.Rows[k + i * pagesize]["xm"].ToString();
                            dt.Rows.Add(dr);
                        }
                    }
                    else
                    {
                        //偶数页
                        for (k = 0; k < rows - (pagecount - 1) * pagesize; k++)
                        {

                            dt.Rows[k + (i / 2) * pagesize]["xh2"] = table.Rows[k + i * pagesize]["xh"].ToString();
                            dt.Rows[k + (i / 2) * pagesize]["xm2"] = table.Rows[k + i * pagesize]["xm"].ToString();

                        }
                    }
                }
            }

                
            return dt;

        }