Question

It seems for removing a TreeNode i have to traverse to it’s parent hence i did below just to find the original collection was modified even though it was a instance. Below is the code and tvRightTree is the TreeView of interest

TreeNodeCollection checkedNodeCollection = tvRightTree.CheckedNodes;
foreach (TreeNode checkedNode in checkedNodeCollection) {
  //if the to be removed node is parent then remove through treeview
  if (checkedNode.Parent != null) {
    //compiler does not allow modifying a collection that we iterate
    //hence resort to finding the parent and then remove
    TreeNode targetParent = tvRightTree.FindNode(checkedNode.Parent.ValuePath);
    targetParent.ChildNodes.Remove(checkedNode);
  } else
    tvRightTree.Nodes.Remove(checkedNode);
  }

What is the correct way to remove checked TreeNodes from the treeview?

Answer 1

You can avoid that error by using

for 

instead of foreach you use now, or use LINQ's ForEach, for example

for(int i=0;i<checkedNodeCollection.Count;i++)
{
    Treenode checkedNode = checkedNodeCollection[i]; 
    .... 
    ..  
}