private void findDialog1_SearchRequested(object sender, SearchEventArgs e)
{
if (e.FirstSearch)
{
// Store the selection start position on the first search so that when all searches are complete
// this fact can be reported to the user in the find dialog.
originalSelectionStart = SelectedNode;
}
// First part of search is between item after current selection (inclusive) and the end of the
// document (exclusive), or the original search position position (exclusive) if this is greater
// than the current selection position
TreeNode searchFromBelow = SelectedNode;
TreeSearchState treeSearchState = TreeSearchState.NotStarted;
// A SubSearch function is used to search part of the tree
SubSearch(e.SearchRegularExpression, Nodes, searchFromBelow, originalSelectionStart, ref treeSearchState);
if (treeSearchState == TreeSearchState.MatchMade)
{
e.Successful = true;// We have a match
}
else if (treeSearchState != TreeSearchState.HitEndNode)
{
// No match? We hit end of document
// Retry from the beginning if the original start position is before or equal to the current selection
e.RestartedFromDocumentTop = true; // The user is informed that the search started from the top
treeSearchState = TreeSearchState.Started;
// Search first half of the document
SubSearch(e.SearchRegularExpression, Nodes, null, originalSelectionStart, ref treeSearchState);
if (treeSearchState == TreeSearchState.MatchMade)
{
e.Successful = true; // We have a match
}
}
}
/// <summary>
/// A recursive 'sub search' command is used to search part of the tree
/// </summary>
/// <param name="regularExpression">The regular expression to use to match text</param>
/// <param name="treeNodeCollection">The collection of nodes to search down from</param>
/// <param name="startAfterNode">The node that searching actually begins from
/// (otherwise just walk the tree until this node is found)</param>
/// <param name="stopAtNode">A node to terminate the search at</param>
/// <param name="state">Sends and returns the state of the recursive search</param>
private void SubSearch(Regex regularExpression, TreeNodeCollection treeNodeCollection, TreeNode startAfterNode, TreeNode stopAtNode, ref TreeSearchState state)
{
foreach (TreeNode treeNode in treeNodeCollection)
{
if (state == TreeSearchState.Started) // Has the search started?
{
if (treeNode == stopAtNode)
{
state = TreeSearchState.HitEndNode;
return;
}
if (nodeSearcher(treeNode, regularExpression))
{
// We need to show search results even when the FindDialog is active
// This means turning off HideSelection if it is set.
// This unfortunately causes a slight flicker. One way to avoid this is to turn off HideSelection
// in individual control instances.
if (HideSelection)
{
// Ensure that the property is restored when the FindDialog is deactivated
findDialog1.Deactivate += new EventHandler(RestoreHideSelection);
HideSelection = false;
}
SelectedNode = treeNode;
SelectedNode.EnsureVisible(); // Make sure the result node is visible
state = TreeSearchState.MatchMade;
return;
}
}
if (startAfterNode == treeNode)
{
state = TreeSearchState.Started;
}
// sub search child nodes
SubSearch(regularExpression, treeNode.Nodes, startAfterNode, stopAtNode, ref state);
if (state == TreeSearchState.HitEndNode)
{
return;
}
if (state == TreeSearchState.MatchMade)
{
return;
}
}
}