/// <summary>
/// The classical approach. The rotation is made based on "pco" value
/// </summary>
/// <param name="oldTable"></param>
/// <param name="pco"></param>
/// <returns></returns>
public static DataTable RotateTable(DataTable oldTable, int pco = 0)
{
var newTable = new DataTable();
if (pco > oldTable.Columns.Count)
{
pco = 0;
}
newTable.Columns.Add(oldTable.Columns[pco].ColumnName);
int counter = 0;
foreach (DataRow row in oldTable.Rows)
{
string newName = row[pco].ToString();
if (newTable.Columns.Contains(newName))
{
newName += "_" + counter.ToString().Trim();
}
newTable.Columns.Add(newName);
counter += 1;
}
for (int col = 0; col <= oldTable.Columns.Count - 1; col++)
{
if (col == pco)
{
continue;
}
var dr = newTable.NewRow();
dr[0] = oldTable.Columns[col].ColumnName;
for (var row = 0; row <= oldTable.Rows.Count - 1; row++)
{
if (StringExtensions.IsNullOrWhiteSpace(oldTable.Rows[row][col].ToString()))
{
dr[row + 1] = DBNull.Value;
continue;
}
if (oldTable.Rows[row][col].ToString().Equals("System.Byte[]"))
{
dr[row + 1] = ByteArrayToString((byte[])oldTable.Rows[row][col]);
}
else if (oldTable.Columns[col].DataType.ToString().Equals("System.DateTime"))
{
dr[row + 1] = Convert.ToDateTime(oldTable.Rows[row][col]).ToString("yyyy-MM-dd HH:mm:ss.fff");
}
else
{
dr[row + 1] = oldTable.Rows[row][col];
}
}
newTable.Rows.Add(dr);
}
return(newTable);
}
/// <summary>
/// Transposing the result with custom or generic header
/// </summary>
/// <param name="oldTable">The datatable object to transform</param>
/// <param name="columnMapping">The custom header</param>
/// <returns></returns>
public static DataTable RotateTableWithKeyValue(DataTable oldTable, string columnMapping)
{
var newTable = new DataTable();
var dr = default(DataRow);
// The column mapping is not provided,so create the generic header
if (columnMapping == null)
{
//the first column name is key
newTable.Columns.Add("Key");
var no = 0;
foreach (DataRow row in oldTable.Rows)
{
newTable.Columns.Add("Value" + (no == 0 ? "" : no.ToString().Trim()));
no++;
}
}
else
{
var names = columnMapping.Split(',');
foreach (var s in names)
{
newTable.Columns.Add(s);
}
// if we do not pass "enough" names, fill the rest with generic names
if (names.Length < oldTable.Rows.Count + 1)
{
var no = names.Length;
while (no < oldTable.Rows.Count + 1)
{
newTable.Columns.Add("Value" + no.ToString().Trim());
no++;
}
}
}
for (var col = 0; col <= oldTable.Columns.Count - 1; col++)
{
dr = newTable.NewRow();
dr[0] = oldTable.Columns[col].ColumnName;
for (var row = 0; row <= oldTable.Rows.Count - 1; row++)
{
if (StringExtensions.IsNullOrWhiteSpace(oldTable.Rows[row][col].ToString()))
{
dr[row + 1] = DBNull.Value;
continue;
}
if (oldTable.Rows[row][col].ToString().Equals("System.Byte[]"))
{
dr[row + 1] = ByteArrayToString((byte[])oldTable.Rows[row][col]);
}
else if (oldTable.Columns[col].DataType.ToString().Equals("System.DateTime"))
{
dr[row + 1] = Convert.ToDateTime(oldTable.Rows[row][col]).ToString("yyyy-MM-dd HH:mm:ss.fff");
}
else
{
dr[row + 1] = oldTable.Rows[row][col];
}
}
newTable.Rows.Add(dr);
}
return(newTable);
}
