.NET DataTable合并成一个DataTable

/// <summary>
        /// 两个结构一样的DT合并
        /// </summary>
        /// <returns></returns>
        public DataTable DtJoinDt(DataTable dt1 = null, DataTable dt2 = null)
        {
            DataTable DataTable1 = dt1;
            DataTable DataTable2 = dt2;
            DataTable newDataTable = DataTable1.Clone();

            object[] obj = new object[newDataTable.Columns.Count];
            for (int i = 0; i < DataTable1.Rows.Count; i++)
            {
                DataTable1.Rows[i].ItemArray.CopyTo(obj, 0);
                newDataTable.Rows.Add(obj);
            }

            for (int i = 0; i < DataTable2.Rows.Count; i++)
            {
                DataTable2.Rows[i].ItemArray.CopyTo(obj, 0);
                newDataTable.Rows.Add(obj);
            }
            return newDataTable;
        }
        /// <summary>
        /// 将两个列不同的DataTable合并成一个新的DataTable
        /// </summary>
        /// <param name="dt1">表1</param>
        /// <param name="dt2">表2</param>
        /// <param name="DTName">合并后新的表名</param>
        /// <returns></returns>
        private DataTable UniteDataTable(DataTable dt1, DataTable dt2, string DTName)
        {
            DataTable dt3 = dt1.Clone();
            for (int i = 0; i < dt2.Columns.Count; i++)
            {
                dt3.Columns.Add(dt2.Columns[i].ColumnName);
            }
            object[] obj = new object[dt3.Columns.Count];

            for (int i = 0; i < dt1.Rows.Count; i++)
            {
                dt1.Rows[i].ItemArray.CopyTo(obj, 0);
                dt3.Rows.Add(obj);
            }

            if (dt1.Rows.Count >= dt2.Rows.Count)
            {
                for (int i = 0; i < dt2.Rows.Count; i++)
                {
                    for (int j = 0; j < dt2.Columns.Count; j++)
                    {
                        dt3.Rows[i][j + dt1.Columns.Count] = dt2.Rows[i][j].ToString();
                    }
                }
            }
            else
            {
                DataRow dr3;
                for (int i = 0; i < dt2.Rows.Count - dt1.Rows.Count; i++)
                {
                    dr3 = dt3.NewRow();
                    dt3.Rows.Add(dr3);
                }
                for (int i = 0; i < dt2.Rows.Count; i++)
                {
                    for (int j = 0; j < dt2.Columns.Count; j++)
                    {
                        dt3.Rows[i][j + dt1.Columns.Count] = dt2.Rows[i][j].ToString();
                    }
                }
            }
            dt3.TableName = DTName; //设置DT的名字
            return dt3;
        }