Document doc = new Document(path);

            DocumentBuilder builder1 = new DocumentBuilder(doc);

            builder1.MoveToBookmark("zyb");

            builder1.RowFormat.Alignment = RowAlignment.Center;//用这个效果居然是整个表格在页面居中...

            builder1.InsertCell();

            builder1.CellFormat.Width = 50;

            builder1.Write("表头1");

            builder1.InsertCell();

            builder1.CellFormat.Width = 100;

            builder1.Write("表头2");

            builder1.InsertCell();

            builder1.CellFormat.Width = 360;

            builder1.Write("表头3");

            builder1.EndRow();

            for (int i = 0; i < 25; i++)

            {

                builder1.InsertCell();

                builder1.CellFormat.Width = 50;

                builder1.Write("列1" + i);

                builder1.InsertCell();

                builder1.CellFormat.Width = 100;

                builder1.Write("列2" + i);

                builder1.InsertCell();

                builder1.CellFormat.Width = 360;

                builder1.Write("列3" + i);