public DataTable ToTable(string tablename, bool isDistinct, params string[] columnNames)
{
if (columnNames == null)
{
throw new ArgumentNullException("columnNames", "'columnNames' argument cannot be null.");
}
DataTable newTable = new DataTable(tablename);
DataColumn[] columns;
ListSortDirection[] sortDirection = null;
if (columnNames.Length != 0)
{
columns = new DataColumn [columnNames.Length];
for (int i = 0; i < columnNames.Length; ++i)
{
columns [i] = Table.Columns [columnNames [i]];
}
if (sortColumns != null)
{
sortDirection = new ListSortDirection [columnNames.Length];
for (int i = 0; i < columnNames.Length; ++i)
{
sortDirection [i] = ListSortDirection.Ascending;
for (int j = 0; j < sortColumns.Length; ++j)
{
if (sortColumns [j] != columns [i])
{
continue;
}
sortDirection [i] = sortOrder [j];
}
}
}
}
else
{
columns = (DataColumn[])Table.Columns.ToArray(typeof(DataColumn));
sortDirection = sortOrder;
}
ArrayList expressionCols = new ArrayList();
for (int i = 0; i < columns.Length; ++i)
{
DataColumn col = columns [i].Clone();
if (col.Expression != String.Empty)
{
col.Expression = "";
expressionCols.Add(col);
}
if (col.ReadOnly)
{
col.ReadOnly = false;
}
newTable.Columns.Add(col);
}
DataRow [] rows;
Index index = new Index(new Key(Table, columns, sortDirection, RowStateFilter, rowFilterExpr));
if (isDistinct)
{
rows = index.GetDistinctRows();
}
else
{
rows = index.GetAllRows();
}
foreach (DataRow row in rows)
{
DataRow newRow = newTable.NewNotInitializedRow();
newTable.Rows.AddInternal(newRow);
newRow.Original = -1;
if (row.HasVersion(DataRowVersion.Current))
{
newRow.Current = newTable.RecordCache.CopyRecord(Table, row.Current, -1);
}
else if (row.HasVersion(DataRowVersion.Original))
{
newRow.Current = newTable.RecordCache.CopyRecord(Table, row.Original, -1);
}
foreach (DataColumn col in expressionCols)
{
newRow [col] = row [col.ColumnName];
}
newRow.Original = -1;
}
return(newTable);
}