public Cursor(AppendRowsDataView parent, IEnumerable <Schema.Column> columnsNeeded)
: base(parent)
{
_currentSourceIndex = 0;
_currentCursor = Sources[_currentSourceIndex].GetRowCursor(columnsNeeded);
_currentIdGetter = _currentCursor.GetIdGetter();
foreach (var col in columnsNeeded)
{
Getters[col.Index] = CreateGetter(col.Index);
}
}
public Cursor(AppendRowsDataView parent, Func <int, bool> needCol)
: base(parent)
{
Ch.AssertValue(needCol);
_currentSourceIndex = 0;
_currentCursor = Sources[_currentSourceIndex].GetRowCursor(needCol);
_currentIdGetter = _currentCursor.GetIdGetter();
for (int c = 0; c < Getters.Length; c++)
{
if (needCol(c))
{
Getters[c] = CreateGetter(c);
}
}
}
protected override bool MoveNextCore()
{
Ch.AssertValue(_currentCursor);
while (!_currentCursor.MoveNext())
{
// Mark the current cursor as finished.
_currentCursor.Dispose();
_currentCursor = null;
if (++_currentSourceIndex >= Sources.Length)
{
return(false);
}
_currentCursor = Sources[_currentSourceIndex].GetRowCursor(c => IsColumnActive(c));
_currentIdGetter = _currentCursor.GetIdGetter();
}
return(true);
}