private void UpdateMultiselection(TreeNode node)
{
bool bControl = (ModifierKeys == Keys.Control);
bool bShift = (ModifierKeys == Keys.Shift);
if (bControl)
{
if (mySelectedNodes.Contains(node))
{
mySelectedNodes.Remove(node);
}
else
{
mySelectedNodes.Add(node);
}
}
else if (bShift)
{
Queue myQueue = new Queue();
TreeNode uppernode = myFirstMultiSelectNode;
TreeNode bottomnode = node;
// case 1 : begin and end nodes are parent
bool bParent = IsParent(myFirstMultiSelectNode, node); // is m_firstNode parent (direct or not) of e.Node
if (!bParent)
{
bParent = IsParent(bottomnode, uppernode);
if (bParent) // swap nodes
{
TreeNode t = uppernode;
uppernode = bottomnode;
bottomnode = t;
}
}
if (bParent)
{
if (uppernode != null)
{
TreeNode n = bottomnode;
while (n != uppernode.Parent)
{
if (!mySelectedNodes.Contains(n)) // new node ?
{
myQueue.Enqueue(n);
}
n = n.Parent;
}
}
}
// case 2 : nor the begin nor the end node are descendant one another
else
{
if ((uppernode.Parent == null && bottomnode.Parent == null) || (uppernode.Parent != null && uppernode.Parent.Nodes.Contains(bottomnode))) // are they siblings ?
{
int nIndexUpper = uppernode.Index;
int nIndexBottom = bottomnode.Index;
if (nIndexBottom < nIndexUpper) // reversed?
{
TreeNode t = uppernode;
uppernode = bottomnode;
bottomnode = t;
nIndexUpper = uppernode.Index;
nIndexBottom = bottomnode.Index;
}
TreeNode n = uppernode;
while (nIndexUpper <= nIndexBottom)
{
if (!mySelectedNodes.Contains(n)) // new node ?
{
myQueue.Enqueue(n);
}
n = n.NextNode;
nIndexUpper++;
} // end while
}
else
{
if (!mySelectedNodes.Contains(uppernode))
{
myQueue.Enqueue(uppernode);
}
if (!mySelectedNodes.Contains(bottomnode))
{
myQueue.Enqueue(bottomnode);
}
}
}
mySelectedNodes.AddRange(myQueue);
myFirstMultiSelectNode = node; // let us chain several SHIFTs if we like it
}
else if (myLastMouseButton != MouseButtons.Right) // don't clear selection when popup menu is invoked
{
// in the case of a simple click, just add this item
if (mySelectedNodes != null && mySelectedNodes.Count > 0)
{
mySelectedNodes.Clear();
}
mySelectedNodes.Add(node);
}
}
