/// <summary>
/// BackgroundWorker method used to create a datatable including data queried from Databasein in all the fields selected.
/// </summary>
/// <param name="parameters"> BackgroundWorker parameters passed from Export Button Click Event</param>
/// <param name="exportdlgWorker"> BackgroundWorker (may be null), in order to show progress</param>
/// <param name="e">Arguments from a BackgroundWorker (may be null), in order to support canceling</param>
/// <returns>Return the BackgroundWorker result.</returns>
private string Exportdlg(BwParameters parameters, BackgroundWorker exportdlgWorker, DoWorkEventArgs e)
{
if (ExportThemes)
{
return(ExportDataSeriesTable(parameters, exportdlgWorker, e));
}
return(ExportAnyDataTable(parameters, exportdlgWorker, e));
}
/// <summary>
/// Export data using BackgroundWorker. Build series table and pass parameters from here to BackgroundWorker.
/// </summary>
private void btnExport_Click(object sender, EventArgs e)
{
// Make sure we aren't still working on a previous task
if (bgwMain.IsBusy)
{
MessageBox.Show("The background worker is busy now. Please try later.", "Export To Text File",
MessageBoxButtons.OK, MessageBoxIcon.Information);
return;
}
//Check the themes for export. There should be at least one item selected.
if (ExportThemes && clbThemes.CheckedItems.Count == 0)
{
MessageBox.Show("Please choose at least one theme to export", "Export To Text File",
MessageBoxButtons.OK, MessageBoxIcon.Information);
return;
}
//Check the desired fields for export. There should be at least one item selected.
if (clbExportItems.CheckedItems.Count == 0)
{
MessageBox.Show("Please choose at least one field to export", "Export To Text File",
MessageBoxButtons.OK, MessageBoxIcon.Information);
return;
}
//Check whether a delimiter is checked
var delimiter = delimiterSelector1.CurrentDelimiter;
if (String.IsNullOrEmpty(delimiter))
{
MessageBox.Show("Please input delimiter.", "Export To Text File");
return;
}
//Check the output file path
string outputFilename = tbOutPutFileName.Text.Trim();
if (outputFilename == String.Empty)
{
MessageBox.Show("Please specify output filename", "Export To Text File");
return;
}
if (Directory.Exists(Path.GetDirectoryName(outputFilename)) == false)
{
MessageBox.Show("The directory for the output filename does not exist", "Export To Text File");
return;
}
// Construct DataTable of all the series in the selected theme
DataTable dtSeries;
if (ExportThemes)
{
var themeIds =
(from ThemeDescription themeDescr in clbThemes.CheckedItems select themeDescr.ThemeId).ToList();
var repository = RepositoryFactory.Instance.Get <IDataSeriesRepository>();
dtSeries = repository.GetSeriesIDsWithNoDataValueTable(themeIds);
}
else
{
dtSeries = _dataToExport;
}
var checkedItems = new List <string>();
foreach (var item in clbExportItems.CheckedItems.Cast <string>().Where(item => !checkedItems.Contains(item)))
{
checkedItems.Add(item);
}
DatesRange datesRange = null;
if (chbUseDateRange.Checked && cmbDateTimeColumns.SelectedIndex >= 0)
{
datesRange = new DatesRange
{
ColumnName = cmbDateTimeColumns.SelectedItem.ToString(),
StartDate = dtpStartDateRange.Value,
EndDate = dtpEndDateRange.Value,
};
}
//Disable all the buttons after "Export" button is clicked.
UpdateControlsState(true);
// Show hourglass
Cursor = Cursors.WaitCursor;
//pass parameters to BackgroundWorker
var parameters = new BwParameters
{
CheckNoData = chkNodata.Checked,
Columns = checkedItems,
DatesRange = datesRange,
Delimiter = delimiter,
OutputFileName = outputFilename,
Series = dtSeries,
};
// Check for overwrite
if (File.Exists(outputFilename))
{
var message = "File " + outputFilename + " already exists.\nWould you like to replace it?";
var replace = MessageBox.Show(message, "Export To Text File", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
if (replace == DialogResult.No)
{
Cursor = Cursors.Default;
// Restore controls to their regular state
UpdateControlsState(false);
return;
}
File.Delete(outputFilename);
bgwMain.RunWorkerAsync(parameters);
}
else
{
bgwMain.RunWorkerAsync(parameters);
}
}
private string ExportAnyDataTable(BwParameters parameters, BackgroundWorker backgroundWorker, DoWorkEventArgs e)
{
var filename = parameters.OutputFileName;
var checkedItems = parameters.Columns;
var delimiter = parameters.Delimiter;
var originalDataTable = parameters.Series;
//Report status
backgroundWorker.ReportProgress(0, "Preparing output...");
DataTable exportDataTable;
if (checkedItems.Count == originalDataTable.Rows.Count)
{
exportDataTable = originalDataTable;
}
else
{
//Build a new datatable to accept selected columns in the original datatable and used to export.
exportDataTable = originalDataTable.Copy(); // copy
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
//Report status
backgroundWorker.ReportProgress(0, "Checking columns...");
//Remove unwanted columns
foreach (DataColumn column in originalDataTable.Columns)
{
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
var columnName = column.ColumnName;
if (!checkedItems.Contains(columnName))
{
exportDataTable.Columns.Remove(columnName);
}
exportDataTable.AcceptChanges();
}
}
// Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
ImportExport.DelimitedTextWriter.DataTableToDelimitedFile(exportDataTable, filename, delimiter,
true, false, backgroundWorker, e,
ImportExport.BackgroundWorkerReportingOptions.UserStateAndProgress);
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
return("Export complete. Rows exported: " + exportDataTable.Rows.Count.ToString(CultureInfo.InvariantCulture));
}
private string ExportDataSeriesTable(BwParameters parameters, BackgroundWorker backgroundWorker, DoWorkEventArgs e)
{
//get parameters
var fileName = parameters.OutputFileName;
var dtSeries = parameters.Series;
var checkNodata = parameters.CheckNoData;
var delimiter = parameters.Delimiter;
var checkedItems = parameters.Columns;
var datesRange = parameters.DatesRange;
var repo = RepositoryFactory.Instance.Get <IDataValuesRepository>();
//export data row by row
for (int r = 0; r < dtSeries.Rows.Count; r++)
{
var row = dtSeries.Rows[r];
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
var noDataValue = !checkNodata?Convert.ToDouble(row["NoDataValue"]) : (double?)null;
// Date range filter
string dateColumn = null;
DateTime?firstDate = null;
DateTime?lastDate = null;
if (datesRange != null)
{
dateColumn = datesRange.ColumnName;
firstDate = datesRange.StartDate;
lastDate = datesRange.EndDate;
}
var tbl = repo.GetTableForExport(Convert.ToInt64(row["SeriesID"]), noDataValue, dateColumn, firstDate,
lastDate);
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
//Construct columns that were selected
for (int i = 0; i < tbl.Columns.Count; i++)
{
var column = tbl.Columns[i];
if (!checkedItems.Contains(column.ColumnName))
{
tbl.Columns.Remove(column);
i--;
}
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
}
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
var includeHeaders = r == 0;
ImportExport.DelimitedTextWriter.DataTableToDelimitedFile(tbl, fileName, delimiter,
includeHeaders, true,
backgroundWorker, e,
ImportExport.BackgroundWorkerReportingOptions.UserStateAndProgress);
//progress report
var percent = (int)(((float)r / dtSeries.Rows.Count) * 100);
var userState = "Writing series " + r + " of " + dtSeries.Rows.Count + "...";
backgroundWorker.ReportProgress(percent, userState);
}
//Check for cancel
if (backgroundWorker.CancellationPending)
{
e.Cancel = true;
return("Data Export Cancelled.");
}
return(dtSeries.Rows.Count.ToString(CultureInfo.InvariantCulture) + " data series downloaded to: " + fileName);
}
