Question

asp.net怎么合并两个table

table1 有2列 和 table2 有2列 合并的效果是 把table2放在table1右边合并后是4列

Answer 1

            DataTable table = new DataTable();
            DataColumn[] cols = new DataColumn[]
            {                
                new DataColumn("ID", typeof(string)),
                new DataColumn("Name", typeof(string)),
                new DataColumn("Birth", typeof(DateTime))
            };
            table.Columns.AddRange(cols);

            for (int i = 0; i < 3; i++)
            {
                DataRow row = table.NewRow();
                row["ID"] = (i + 1).ToString();
                row["Name"] = "stu" + i.ToString();
                row["Birth"] = DateTime.Now.AddYears(-10).AddDays(i);
                table.Rows.Add(row);
            }

            DataTable table2 = new DataTable();
            DataColumn[] cols2 = new DataColumn[]
            {                
                new DataColumn("ID2", typeof(string)),
                new DataColumn("Name2", typeof(string)),
                new DataColumn("Birth2", typeof(DateTime))
            };
            table2.Columns.AddRange(cols2);

            for (int i = 0; i < 3; i++)
            {
                DataRow row = table2.NewRow();
                row["ID2"] = (i + 1).ToString();
                row["Name2"] = "stu" + i.ToString();
                row["Birth2"] = DateTime.Now.AddYears(-10).AddDays(i);
                table2.Rows.Add(row);
            }

            foreach (DataColumn col in table2.Columns)
            {
                DataColumn colClone = new DataColumn(col.ColumnName, col.DataType);
                table.Columns.Add(colClone);
                
                //主table的数据行数必须>=子table的数据行数
                if (table.Rows.Count >= table2.Rows.Count)
                {
                    for (int i = 0; i < table2.Rows.Count; i++)
                    {
                        table.Rows[i][col.ColumnName] = table2.Rows[i][col.ColumnName];
                    }
                }
            }

追问

能不能加上注释看看？

追答

前面创建table的语句，我相信你懂的。

            //合并table
            foreach (DataColumn col in table2.Columns)
            {
                //克隆table2中的列（一个列对象只能添加入一个table中，所以这里只能克隆一个列对象）
                DataColumn colClone = new DataColumn(col.ColumnName, col.DataType);
                //主table添加table2的列
                table.Columns.Add(colClone);
                 
                //主table的数据行数必须>=子table的数据行数
                if (table.Rows.Count >= table2.Rows.Count)
                {
                    //赋值
                    for (int i = 0; i < table2.Rows.Count; i++)
                    {
                        table.Rows[i][col.ColumnName] = table2.Rows[i][col.ColumnName];
                    }
                }
            }

追问

谢谢，效果已经出来了

追答

K7