IEnumerator^ myEnum = customer2->CustomerOrders->GetEnumerator() Add a child treenode for each Order object in the current Customer object. TreeView1->Nodes->Add( gcnew TreeNode( customer2->CustomerName ) ) Add a root TreeNode for each Customer object in the ArrayList.Ĭustomer^ customer2 = safe_cast(myEnum->Current) Clear the TreeView each time the method is called. Suppress repainting the TreeView until all the objects have been created. ::Cursor::Current = gcnew System::Windows::Forms::Cursor( "MyWait.cur" ) Display a wait cursor while the TreeNodes are being created. IEnumerator^ myEnum = customerArray->GetEnumerator() Ĭustomer^ customer1 = safe_cast(myEnum->Current) įor ( int y = 0 y CustomerOrders->Add( gcnew Order( "Order " + y ) ) Add orders to each Customer object in the ArrayList. Add customers to the ArrayList of Customer objects.įor ( int x = 0 x Add( gcnew Customer( "Customer " + x ) ) Ref class Customer: public System::Object It also requires that you have a cursor file that is named MyWait.cur in the application directory and that you have created an instance of a TreeView control on a Form. This example requires that you have a Customer object that can hold a collection of Order objects. The repainting of the TreeView is suppressed by using the BeginUpdate and EndUpdate methods, and a wait Cursor is displayed while the TreeView creates and paints the TreeNode objects. In this example, 1,000 customers are displayed with 15 orders each. The root tree nodes display customer names, and the child tree nodes display the order numbers assigned to each customer. The following, more complex code example displays customer information in a TreeView control. TreeView1.Nodes(0).Nodes(1).Nodes(0).Nodes.Add("Great Grandchild") TreeView1.Nodes(0).Nodes(1).Nodes.Add("Grandchild") ' Populates a TreeView control with example nodes. ![]() Populates a TreeView control with example nodes. The following code example demonstrates the use of the TreeView control. Public class TreeView : type TreeView = classĬlassInterfaceAttribute ComVisibleAttribute DockingAttribute Examples In this article public ref class TreeView : System::Windows::Forms::Control public class TreeView : Therefore the application could not find the parent for node A1 and A2.Displays a hierarchical collection of labeled items, each represented by a TreeNode. This way, my application will try to populate A1 and A2 nodes into the tree even before node A is created. This is because when I sort the rows based on ParentID prior to populating the treeview, the rows are sorted like this: ID Name ParentID The next time I run the application, it fails to populate node A1 and A2 into the tree because it could not find their parents. Now my database table looks like this: ID Name ParentID continue to look for parent recursivelyįoreach (TreeNode n in potentialParent.Nodes)Īll is well until I drag-and-drop the nodes by making node A the child of node C and commit the changes to the database. update that the parent for child has been found ![]() If (parentID.CompareTo(potentialParent.Name) = 0) am i the parent that you're looking for? Private void TraverseParent(TreeNode potentialParent, String parentID, TreeNode node) TreeNodeCollection collection = tree.Nodes Post: call TraverseParent method to search parent I populate the tree view using these two methods (TreeNode node here is the childnode that is being populated into the tree): private void SearchParent(TreeView tree, String parentID, TreeNode node) I sort the rows by ParentID prior to populating the treeview. E.g., Node A, B and C are root node's children. ParentID equals to "0" means that the node's parent is the root node (hardcoded). ![]() This table shows that node A is the parent node for node A1 and A2. ![]() This is how my table looks like: ID Name ParentID Name column contain string that will be the treenode's Text attribute, while ParentID is a column contains the node's parent ID. ID will also be the node's Name properties. The ID column contains running number which also serves as the primary key. I have a table with 3 columns, ID, Name and ParentID.
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