// sheet grid data
public static IList <IList <string> > GetDataAsStringsGrid(this Sheet sheet, int columnsRequired, int rowsRequired)
{
// Create empty sheet strings grid placeholder with required
// number of the empty spaces for each row.
IList <IList <string> > sheetStringsGrid = new IList <string> [rowsRequired];
// Foreach row
for (int rIndex = 0; rIndex < rowsRequired; rIndex++)
{
// Obtain row data if any available.
RowData row = sheet.Data?.ElementAtOrDefault(0)?.RowData?.ElementAtOrDefault(rIndex);
// If row data is available for this specific row.
if (!(row is null) && !(row.Values is null))
{
// Allocate appropriate size list filled with the data
// obtained from the row data on the sheet strings grid.
sheetStringsGrid[rIndex] = row.GetDataAsStrings(columnsRequired);
}