protected IEnumerable <RowItem> Filter(CancellationToken cancellationToken, DataSchema dataSchema, RowFilter filter, PivotedRows pivotedRows)
{
if (filter.IsEmptyFilter)
{
return(pivotedRows.RowItems);
}
var properties = pivotedRows.ItemProperties;
Predicate <object>[] columnPredicates = new Predicate <object> [properties.Count];
for (int i = 0; i < properties.Count; i++)
{
columnPredicates[i] = filter.GetPredicate(dataSchema, properties[i]);
}
var filteredRows = new List <RowItem>();
// toString on an enum is incredibly slow, so we cache the results in
// in a dictionary.
var toStringCaches = new Dictionary <object, string> [properties.Count];
for (int i = 0; i < properties.Count; i++)
{
var property = properties[i];
if (property.PropertyType.IsEnum)
{
toStringCaches[i] = new Dictionary <object, string>();
}
}
foreach (var row in pivotedRows.RowItems)
{
bool matchesText = string.IsNullOrEmpty(filter.Text);
bool matchesFilter = true;
for (int iProperty = 0; iProperty < properties.Count; iProperty++)
{
cancellationToken.ThrowIfCancellationRequested();
var predicate = columnPredicates[iProperty];
if (matchesText && null == predicate)
{
continue;
}
var property = properties[iProperty];
var value = property.GetValue(row);
if (!matchesText && value != null)
{
var cache = toStringCaches[iProperty];
string strValue;
if (cache == null)
{
strValue = value.ToString();
}
else
{
if (!cache.TryGetValue(value, out strValue))
{
strValue = value.ToString();
cache.Add(value, strValue);
}
}
if (filter.MatchesText(strValue))
{
matchesText = true;
}
}
matchesFilter = null == predicate || predicate(value);
if (!matchesFilter)
{
break;
}
}
if (matchesText && matchesFilter)
{
filteredRows.Add(row);
}
}
if (filteredRows.Count == pivotedRows.RowItems.Count)
{
return(pivotedRows.RowItems);
}
return(filteredRows);
}
