C#中连接DataTable的方法

C#中连接DataTable的方法(2)                 //创建关联

                DataRelation r = new DataRelation(string.Empty,parentcolumns,childcolumns,false);

                ds.Relations.Add(r);

                //为关联表创建列

                for(int i = 0; i < First.Columns.Count; i++)

                {

                    table.Columns.Add(First.Columns[i].ColumnName, First.Columns[i].DataType);

                }

                for(int i = 0; i < Second.Columns.Count; i++)

                {

                    //看看有没有重复的列，如果有在第二个DataTable的Column的列明后加_Second

                    if(!table.Columns.Contains(Second.Columns[i].ColumnName))

                        table.Columns.Add(Second.Columns[i].ColumnName, Second.Columns[i].DataType);

                    else

                        table.Columns.Add(Second.Columns[i].ColumnName + "_Second", Second.Columns[i].DataType);

                }