/// <summary>
/// Extracts the complete html table the given path is pointing to. If the path points
/// to a cell of a table the complete table is extracted still.
/// <remarks>
/// Returns null if table not found by path. Currently we cannot handle thead
/// and tfoot. The number of the column is defined by the html table row with the most
/// html columns
/// </remarks>
/// </summary>
/// <param name="doc">the HTML document</param>
/// <param name="path">the path to the table</param>
/// <param name="textOnly">set this to true to get only the text of the cell, otherwise the
/// cell itself as HtmlElement is returned</param>
public static FallibleActionResult <DataTable> ExtractTable(this IHtmlDocument doc, HtmlPath path, bool textOnly)
{
doc.Require(x => doc != null);
path.Require(x => path != null);
HtmlTable htmlTable = doc.GetTableByPath(path);
if (htmlTable == null)
{
return(FallibleActionResult <DataTable> .CreateFailureResult("Could not get table by path"));
}
DataTable table = new DataTable();
// TODO: should we get the culture from the HTML page somehow?
table.Locale = CultureInfo.InvariantCulture;
Func <IHtmlElement, object> GetContent = element => (textOnly ? (object)element.InnerText : element);
foreach (var tr in htmlTable.Rows)
{
var htmlRow = new List <IHtmlElement>();
foreach (var td in tr.Children)
{
if (td.TagName == "TD" || td.TagName == "TH")
{
htmlRow.Add(td);
}
}
// add columns if necessary
if (htmlRow.Count > table.Columns.Count)
{
(htmlRow.Count - table.Columns.Count).Times(x => table.Columns.Add(string.Empty, typeof(object)));
}
// add new row to table
DataRow row = table.NewRow();
table.Rows.Add(row);
table.AcceptChanges();
// add data
htmlRow.ForeachIndex((element, idx) => row[idx] = GetContent(element));
}
if (table.Rows.Count == 0)
{
table.Dispose();
return(FallibleActionResult <DataTable> .CreateFailureResult("Table was empty"));
}
return(FallibleActionResult <DataTable> .CreateSuccessResult(table));
}
/// <summary>
/// Extracts a cell or a series of the html table the given path is pointing to.
/// If the path points to the table element itself instead of a cell the whole table will be
/// extracted.
/// The series to be extracted is always arranged in a column (independed of the original layout
/// in the html table). The first column contains the values, the second the series header (if
/// any defined). The series name is stored in the ColumnName of the first column.
/// <remarks>
/// Returns null if table not found by path. Currently we cannot handle thead
/// and tfoot.
/// </remarks>
/// </summary>
/// <param name="path">points to a cell or the body of a table (pointers to TR elements are invalid)</param>
/// <param name="doc">the HTML document</param>
/// <param name="htmlSettings">the HTML settings used to configure the extraction process</param>
/// <param name="tableSettings">the table specific configuration</param>
public static FallibleActionResult <DataTable> ExtractTable(this IHtmlDocument doc, HtmlPath path, TableExtractionSettings tableSettings, HtmlExtractionSettings htmlSettings)
{
if (!path.PointsToTable && !path.PointsToTableCell)
{
throw new InvalidExpressionException("Path neither points to table nor to cell");
}
FallibleActionResult <DataTable> result = ExtractTable(doc, path, !htmlSettings.ExtractLinkUrl);
if (!result.Success)
{
// pass throu failure result
return(result);
}
// path points to whole table => return whole table
if (path.PointsToTable)
{
return(result);
}
// get the x,y position of the cell the path is pointing to
Point cellCoords = path.GetTableCellPosition();
if (cellCoords.X < 0 || cellCoords.Y < 0)
{
throw new InvalidExpressionException("Path expression corrupt: cell position in table could not be calculated");
}
// get the value of the raw cell. extract the link url if configured.
Func <object, object> GetValue = e =>
{
if (htmlSettings.ExtractLinkUrl)
{
return(((IHtmlElement)e).FirstLinkOrInnerText());
}
else
{
return(e);
}
};
var t = result.Value.ExtractSeries(cellCoords, GetValue, tableSettings);
if (t == null)
{
return(FallibleActionResult <DataTable> .CreateFailureResult("Could not extract series specified"));
}
return(FallibleActionResult <DataTable> .CreateSuccessResult(t));
}
