protected override void PerformSearch(string searchTerm, CancellationToken token, ComboTreeNodeCollection results)
{
string adoFilter = String.Format("Word LIKE '{0}%'", searchTerm.Replace("'", "''"));
foreach (DataRow dr in _table.Select(adoFilter))
{
token.ThrowIfCancellationRequested();
results.Add(new ComboTreeNode(dr.Field <string>(0)));
}
}
private void AddNode(ComboTreeNodeCollection nodes, KindOfGoods kind)
{
var node = new ComboTreeNode(kind.Name)
{
Tag = kind, Expanded = true
};
nodes.Add(node);
kind.SubKinds.ForEach(k => this.AddNode(node.Nodes, k));
}
void dsbListItems_PerformSearch(object sender, PerformSearchEventArgs e)
{
if (chkRetainGroups.Checked)
{
foreach (ComboTreeNode node in dsbListItems.AllNormalNodes)
{
e.CancellationToken.ThrowIfCancellationRequested();
if (dsbListItems.DefaultSearchPredicate(node, e.SearchTerm))
{
// get all ancestor nodes (including the result)
Stack <ComboTreeNode> ancestors = new Stack <ComboTreeNode>();
ComboTreeNode current = node;
while (current != null)
{
ancestors.Push(current);
current = current.Parent;
}
// copy ancestor nodes into search results (or re-use existing)
ComboTreeNodeCollection collection = e.Results;
while (ancestors.Any())
{
current = ancestors.Pop();
ComboTreeNode copy = e.Results.Find(x => dsbListItems.DefaultEquivalencePredicate(x, current), true);
if (copy == null)
{
collection.Add(copy = current.Clone());
}
collection = copy.Nodes;
}
}
}
e.Handled = true;
}
}
void _services_TextChanged(object sender, EventArgs e)
{
// cancel any existing search operation
if (_cts != null)
{
_cts.Cancel();
_cts.Dispose();
_cts = null;
}
if (_services.Length > 0)
{
if (!_inSearchMode)
{
EnterSearchMode();
}
if (_services.Length >= MinSearchTermLength)
{
// start async search operation
BeginUpdate();
Nodes.Clear();
Nodes.Add(new ComboTreeNode("Searching...")
{
Selectable = false, FontStyle = FontStyle.Italic
});
EndUpdate();
_cts = new CancellationTokenSource();
ComboTreeNodeCollection results = new ComboTreeNodeCollection(null);
var task = Task.Factory.StartNew(() => OnPerformSearch(new PerformSearchEventArgs(_services.Text, _cts.Token, results)), _cts.Token);
task.ContinueWith(t => {
if (t.IsFaulted)
{
results.Clear();
string errorText = t.Exception.InnerExceptions.Select(x => x.Message).FirstOrDefault() ?? "an error occured";
results.Add(new ComboTreeNode(String.Format("({0})", errorText))
{
Selectable = false, FontStyle = FontStyle.Italic
});
}
if (!t.IsCanceled)
{
ApplySearchResults(results);
}
});
}
else
{
// wait until the search term is long enough
BeginUpdate();
Nodes.Clear();
string msg = String.Format("(type at least {0} characters)", MinSearchTermLength);
Nodes.Add(new ComboTreeNode(msg)
{
Selectable = false, FontStyle = FontStyle.Italic
});
EndUpdate();
}
}
else
{
if (_inSearchMode)
{
LeaveSearchMode(false);
}
}
}