How to rearrange data columns

We can change the ordinal of data column


dataTable.Columns["clmName"].SetOrdinal(2);

How to create one data table from other datatable

You can create copy of existing data table and than remove unwanted data columns from data table
Following is code:

DataTable dtSourceCopy = dtSource.Copy();
                    DataColumnCollection columnsArray = dtSourceCopy .Columns;
                    foreach (var item in columnsArray)
                    {
                        if (!selectedColumns.Contains(item.ToString()))
                        {
                            dtSource.Columns.Remove(item.ToString());
                        }
                    }