Control Tree View

How to: Adding and Removing Nodes

Create a ControlTreeNode using one of the three constructors

                // Constructor 1: Creates a new ControlTreeNode containing a label with the text
                "New Label"
                
                ControlTreeNode controlTreeNode1 = new ControlTreeNode();
                
                // Constructor 2: Creates a new ControlTreeNode containing a label with the text
                "My Label"
                
                ControlTreeNode controlTreeNode2 = new ControlTreeNode("My Label");
                
                // Constructor 3: Creates a new ControlTreeNode containing a Button
                
                Button b = new Button();
                
                b.Text = "Click me!";
                
                ControlTreeNode controlTreeNode3 = new ControlTreeNode(b);

Add node by using the Add() method

                // Add root node to ControlTreeView 'controlTreeView1'
                
                controlTreeView1.Nodes.Add(controlTreeNode1);
                
                // Add another root node to ControlTreeView 'controlTreeView1'
                
                controlTreeView1.Nodes.Add(controlTreeNode2);
                
                // Add Child node to ControlTreeNode 'controlTreeNode1'
                
                controlTreeNode1.Nodes.Add(controlTreeNode3);

Remove nodes by using the Clear(), Remove() or RemoveAt() methods

                //Remove all Nodes from treeview 'controlTreeView1'
                
                controlTreeView1.Nodes.Clear();

                // Remove all child nodes from node 'controlTreeNode1'
                
                controlTreeNode1.Nodes.Clear();
                
                //Remove first root node from ControlTreeView 'controlTreeView1'
                
                controlTreeView1.Nodes[0].Remove();
                
                //or
                
                controlTreeView1.Nodes.RemoveAt(0);

How to: Adding and removing controls to a ControlTreeNode

Step 1. Create controls

                ComboBox cb = new ComboBox();
                
    cb.Items.Add("Option 1"); 
                
                cb.Items.Add("Option 2"); 
                
                cb.Items.Add("Option 3"); 
                
                CheckedListBox
    clb = new CheckedListBox(); 
                
                clb.Items.Add("List Item 1", false); 
                
                clb.Items.Add("List
    Item 2", true); 
                
                clb.Items.Add("List Item 3", true);

Step2. Create a ControlTreeNode to hold the Controls

                // Assign first control to node when creating ControlTreeNode

    ControlTreeNode controlTreeNode1 = new ControlTreeNode(cb);

    //Add another Control to ControlTreeNode 'controlTreeNode1'
    
    controlTreeNode1.Controls.Add(clb);
                
    //Set Controls layout mode 
    
    controlTreeNode1.FlowDirection = FlowDirection.LeftToRight;
    
                //Add 'controlTreeNode1' to ControlTreeView 'controlTreeView1'

    controlTreeView1.Nodes.Add(controlTreeNode1);

Remove controls by using the Clear(), Remove(Control value) or RemoveAt() methods

    //Removing all Controls from a ControlTreeNode
    
    controlTreeNode1.Controls.Clear();

    //Removing first Control from a ControlTreeNode
    
    controlTreeNode1.Controls.RemoveAt(0);
    
                //Remove ComboBox from ControlTreeNode 'controlTreeNode1'

                controlTreeNode1.Controls.Remove(cb);

How to: Determine which tree node was selected

Which ControlTreeNode is currently selected is stored in the ControlTreeView.SelectedNode Property. The Property's value changes when the user Clicks on a node's border. The selectionborder width (top, bottom, left and right) can be set using the ControlTreeView.NodeSelectBorderWidth property. This value is inherited to all new nodes added to the Treeview. This default value can be changed for individual nodes by using the ControlTreeNode.SelectBorderWidth property.
Note: Setting the selection border width to 0 will disable the Controls automatic node selection functionality. In this case, you will have to select nodes programmatically by reacting to other events e.g. clicked event of a control within the tree node.

Using the ControlTreeView.SelectedNode Property

                //Use the ControlTreeView.SelectedNode
    Property to determine which Node is selected

                ControlTreeNode selectedNode
    = controlTreeView1.SelectedNode;

                //or to set the SelectedNode programatically

    controlTreeView1.SelectedNode = controlTreeView1.Nodes[0];

Events ControlTreeView.BeforeSelect and ControlTreeView.AfterSelect

    //Use the ControlTreeView.BeforeSelect and ControlTreeView.AfterSelect
    events to determine which two nodes are involved in the selection change. 
                
                ControlTreeNode
    selectedNodeBeforeChange; 
                
                ControlTreeNode selectedNodeAfterChange; 
                
                controlTreeView1.BeforeSelect
    += new EventHandler(controlTreeView1_BeforeSelect); 
                
                controlTreeView1.AfterSelect
    += new EventHandler(controlTreeView1_AfterSelect); 

                void controlTreeView1_BeforeSelect(object
    sender, EventArgs e) 
                
                {
                
                    //values of selectedNodeBeforeChange and selectedNodeAfterChange
    are different. 
                
                    selectedNodeBeforeChange = controlTreeView1.SelectedNode;
                
                    selectedNodeAfterChange = (ControlTreeNode)sender;
                
                }
                
                void controlTreeView1_AfterSelect(object sender, EventArgs
    e) 
                
                {
                
                    //values of selectedNodeBeforeChange and selectedNodeAfterChange are the same.
                
                    selectedNodeBeforeChange = controlTreeView1.SelectedNode;
                
                    selectedNodeAfterChange = (ControlTreeNode)sender;
                
                }

How to: Implement Drag and Drop

Drag and Drop operations are implemented using the following 3 events

controlTreeView1.NodeMouseDown
controlTreeView1.NodeDragEnter
controlTreeView1.NodeDragDrop

The following examples allows the user to move nodes within the tree using drag and drop.

                // Subscribe to events

                controlTreeView1.NodeMouseDown += new MouseEventHandler(controlTreeView1_NodeMouseDown);
                
                controlTreeView1.NodeDragEnter += new DragEventHandler(controlTreeView1_NodeDragEnter);
                
                controlTreeView1.NodeDragDrop += new DragEventHandler(controlTreeView1_NodeDragDrop);

                void controlTreeView1_NodeMouseDown(object sender, MouseEventArgs e)
                
                { 

                    //Start Drag and Drop operation when a user clicks on the node's selectionborder

                    controlTreeView1.DoDragDrop(sender, DragDropEffects.Move);
                
                }

                void controlTreeView1_NodeDragEnter(object sender, DragEventArgs e)
                
                {
                
                    //Make sure that a ControlTreeNode object is being draged over the
                destination node.

                    if (e.Data.GetDataPresent("Tawil.Windows.Controls.ControlTreeNode")) 

                    { 

                            // Determine which node is being moved

                        ControlTreeNode dragSource = (ControlTreeNode)e.Data.GetData("Tawil.Windows.Controls.ControlTreeNode"); 

                        // Determine which node is the new parent

                            ControlTreeNode dragDestination = (ControlTreeNode)sender; 

                        // Make sure that source and destination are different

                        if (dragSource == dragDestination) 

                            e.Effect = DragDropEffects.None; 

                        else 

                            e.Effect = DragDropEffects.Move; 

                    }
                
                    else
                
                    {

                        e.Effect = DragDropEffects.None;
                
                    }

                }

                void controlTreeView1_NodeDragDrop(object sender, DragEventArgs e)
                
                {
                
                    try
                
                    { 

                          //Make sure that a ControlTreeNode object
                is being droped over the destination node.

                         if (e.Data.GetDataPresent("Tawil.Windows.Controls.ControlTreeNode"))
                
                         { 

                                  // Determine
                which node is being moved

                             ControlTreeNode dragSource = (ControlTreeNode)e.Data.GetData("Tawil.Windows.Controls.ControlTreeNode"); 

                             // Determine which node is the new
                parent

                             ControlTreeNode dragDestination
                = (ControlTreeNode)sender; 

                             // Make sure that source and destination
                are different

                                   if (dragSource
                != dragDestination)
                
                             {
                
                // Move node

                                 dragSource.ChangeParentNode(dragDestination);
                
                             }
                
                         } 

                    }
                
                    catch (Exception ee) 
                
                    {
                
                        MessageBox.Show(ee.Message);
                
                    }
                
                }