/// <summary>
/// Visits a property reference expression.
/// </summary>
/// <param name="expression">The expression to visit.</param>
public override void VisitPropertyReferenceExpression(PropertyReferenceFilterExpression expression)
{
//This is working around a missing property on the filter api.
//This could can be removed when the issue is resolved.
ODataDataSourceFilterExpressionVisitor v = new ODataDataSourceFilterExpressionVisitor();
v.VisitPropertyReferenceExpression(expression);
string result = v.ToString();
RenderPropertyReference(result);
}
protected override void MakeTaskForRequest(AsyncDataSourcePageRequest request, int retryDelay)
{
int actualPageSize = 0;
SortDescriptionCollection sortDescriptions = null;
lock (SyncLock)
{
actualPageSize = ActualPageSize;
sortDescriptions = SortDescriptions;
}
ODataFeedAnnotations annotations = new ODataFeedAnnotations();
var client = _client.For(_entitySet);
lock (SyncLock)
{
if (FilterExpressions != null &&
FilterExpressions.Count > 0 &&
_filterString == null)
{
StringBuilder sb = new StringBuilder();
bool first = true;
foreach (var expr in FilterExpressions)
{
if (first)
{
first = false;
}
else
{
sb.Append(" AND ");
}
ODataDataSourceFilterExpressionVisitor visitor = new ODataDataSourceFilterExpressionVisitor();
visitor.Visit(expr);
var txt = visitor.ToString();
if (FilterExpressions.Count > 1)
{
txt = "(" + txt + ")";
}
sb.Append(txt);
}
_filterString = sb.ToString();
}
if (_filterString != null)
{
client = client.Filter(_filterString);
}
if (SortDescriptions != null)
{
foreach (var sort in SortDescriptions)
{
if (sort.Direction == System.ComponentModel.ListSortDirection.Descending)
{
client = client.OrderByDescending(sort.PropertyName);
}
else
{
client = client.OrderBy(sort.PropertyName);
}
}
}
if (DesiredProperties != null && DesiredProperties.Length > 0)
{
client = client.Select(DesiredProperties);
}
}
Task task;
if (request.Index == SchemaRequestIndex)
{
task = client
.Count()
.FindScalarAsync<int>();
}
else
{
task = client
.Skip(request.Index * actualPageSize)
.Top(actualPageSize)
.FindEntriesAsync(annotations);
}
request.TaskHolder = new AsyncDataSourcePageTaskHolder();
request.TaskHolder.Task = task;
lock (SyncLock)
{
Tasks.Add(request);
_annotations.Add(annotations);
}
}
