private DataTable ReadData(TxtImportSettings settings, int maxRowsCount)
{
var fileName = settings.PathToFile;
DataTable result;
if (!File.Exists(fileName))
{
result = new DataTable();
}
else
{
switch (settings.FileType)
{
case TxtFileType.Delimited:
result = GetPreviewForDelimitedFile(settings, maxRowsCount);
break;
case TxtFileType.FixedWidth:
result = GetPreviewForFixedWidthFile(settings, maxRowsCount);
break;
default:
result = new DataTable();
break;
}
}
return(result);
}
private static DataTable GetPreviewForDelimitedFile(TxtImportSettings settings, int maxRowsCount)
{
var fileName = settings.PathToFile;
var result = new DataTable();
using (var streamReader = new StreamReader(fileName))
{
while (streamReader.Peek() != -1 &&
(maxRowsCount < 0 ||
result.Rows.Count < maxRowsCount))
{
var line = streamReader.ReadLine();
if (String.IsNullOrEmpty(line))
{
continue;
}
var splitValues = line.Split(new[] { settings.Delimiter }, StringSplitOptions.RemoveEmptyEntries);
if (splitValues.Length == 0)
{
continue;
}
if (result.Columns.Count == 0)
{
foreach (var splitValue in splitValues)
{
result.Columns.Add(splitValue);
}
}
else
{
var row = result.NewRow();
var minColumn = Math.Min(splitValues.Length, result.Columns.Count);
for (int i = 0; i < minColumn; i++)
{
row[i] = splitValues[i];
}
result.Rows.Add(row);
}
}
}
return(result);
}
public FormatOptionsPage(WizardContext context)
{
_settings = (TxtImportSettings)context.Settings;
_importer = context.Importer;
InitializeComponent();
// FileType combo box
cmbFileType.DataSource = Enum.GetValues(typeof(TxtFileType));
cmbFileType.Format += delegate(object s, ListControlConvertEventArgs args)
{
args.Value = ((TxtFileType)args.ListItem).Description();
};
cmbFileType.SelectedValueChanged += CmbFileTypeOnSelectedValueChanged;
cmbFileType.DataBindings.Clear();
cmbFileType.DataBindings.Add("SelectedItem", _settings, "FileType", true, DataSourceUpdateMode.OnPropertyChanged);
// Delimiter
_settings.Delimiter = delimiterSelector.CurrentDelimiter;
delimiterSelector.CurrentDelimiterChanged += DelimiterSelectorOnCurrentDelimiterChanged;
//
CmbFileTypeOnSelectedValueChanged(cmbFileType, EventArgs.Empty);
}
private static DataTable GetPreviewForFixedWidthFile(TxtImportSettings settings, int maxRowsCount)
{
var fileName = settings.PathToFile;
var result = new DataTable();
int[] columnLengths = null;
using (var streamReader = new StreamReader(fileName))
{
while (streamReader.Peek() != -1 &&
(maxRowsCount < 0 ||
result.Rows.Count < maxRowsCount))
{
var line = streamReader.ReadLine();
if (String.IsNullOrEmpty(line))
{
continue;
}
if (columnLengths == null)
{
var columns = line.Split(new[] { " " }, StringSplitOptions.RemoveEmptyEntries);
if (columns.Length == 0)
{
continue;
}
columnLengths = new int[columns.Length];
foreach (var column in columns)
{
result.Columns.Add(column);
}
for (int i = columns.Length - 1; i >= 0; i--)
{
var lastIndex = line.LastIndexOf(columns[i], StringComparison.Ordinal);
var columnLength = line.Length - lastIndex;
columnLengths[i] = columnLength;
line = line.Remove(lastIndex);
}
}
else
{
var row = result.NewRow();
for (int i = 0; i < columnLengths.Length; i++)
{
if (line.Length == 0)
{
break;
}
var curLen = Math.Min(columnLengths[i], line.Length);
var value = line.Substring(0, curLen).Trim();
row[i] = value;
line = line.Substring(curLen);
}
result.Rows.Add(row);
}
}
}
return(result);
}
