TreeNodeCollection Class
Represents a collection of TreeNode objects.
Assembly: System.Windows.Forms (in System.Windows.Forms.dll)
The TreeNodeCollection type exposes the following members.
| Name | Description | |
|---|---|---|
![]() | Count | Gets the total number of TreeNode objects in the collection. |
![]() | IsReadOnly | Gets a value indicating whether the collection is read-only. |
![]() | Item[Int32] | Gets or sets the TreeNode at the specified indexed location in the collection. |
![]() | Item[String] | Gets the tree node with the specified key from the collection. |
| Name | Description | |
|---|---|---|
![]() | Add(String) | Adds a new tree node with the specified label text to the end of the current tree node collection. |
![]() | Add(TreeNode) | Adds a previously created tree node to the end of the tree node collection. |
![]() | Add(String, String) | Creates a new tree node with the specified key and text, and adds it to the collection. |
![]() | Add(String, String, Int32) | Creates a tree node with the specified key, text, and image, and adds it to the collection. |
![]() | Add(String, String, String) | Creates a tree node with the specified key, text, and image, and adds it to the collection. |
![]() | Add(String, String, Int32, Int32) | Creates a tree node with the specified key, text, and images, and adds it to the collection. |
![]() | Add(String, String, String, String) | Creates a tree node with the specified key, text, and images, and adds it to the collection. |
![]() | AddRange | Adds an array of previously created tree nodes to the collection. |
![]() | Clear | Removes all tree nodes from the collection. |
![]() | Contains | Determines whether the specified tree node is a member of the collection. |
![]() | ContainsKey | Determines whether the collection contains a tree node with the specified key. |
![]() | CopyTo | Copies the entire collection into an existing array at a specified location within the array. |
![]() | Equals(Object) | Determines whether the specified Object is equal to the current Object. (Inherited from Object.) |
![]() | Finalize | Allows an object to try to free resources and perform other cleanup operations before it is reclaimed by garbage collection. (Inherited from Object.) |
![]() | Find | Finds the tree nodes with specified key, optionally searching subnodes. |
![]() | GetEnumerator | Returns an enumerator that can be used to iterate through the tree node collection. |
![]() | GetHashCode | Serves as a hash function for a particular type. (Inherited from Object.) |
![]() | GetType | Gets the Type of the current instance. (Inherited from Object.) |
![]() | IndexOf | Returns the index of the specified tree node in the collection. |
![]() | IndexOfKey | Returns the index of the first occurrence of a tree node with the specified key. |
![]() | Insert(Int32, String) | Creates a tree node with the specified text and inserts it at the specified index. |
![]() | Insert(Int32, TreeNode) | Inserts an existing tree node into the tree node collection at the specified location. |
![]() | Insert(Int32, String, String) | Creates a tree node with the specified text and key, and inserts it into the collection. |
![]() | Insert(Int32, String, String, Int32) | Creates a tree node with the specified key, text, and image, and inserts it into the collection at the specified index. |
![]() | Insert(Int32, String, String, String) | Creates a tree node with the specified key, text, and image, and inserts it into the collection at the specified index. |
![]() | Insert(Int32, String, String, Int32, Int32) | Creates a tree node with the specified key, text, and images, and inserts it into the collection at the specified index. |
![]() | Insert(Int32, String, String, String, String) | Creates a tree node with the specified key, text, and images, and inserts it into the collection at the specified index. |
![]() | MemberwiseClone | Creates a shallow copy of the current Object. (Inherited from Object.) |
![]() | Remove | Removes the specified tree node from the tree node collection. |
![]() | RemoveAt | Removes a tree node from the tree node collection at a specified index. |
![]() | RemoveByKey | Removes the tree node with the specified key from the collection. |
![]() | ToString | Returns a string that represents the current object. (Inherited from Object.) |
| Name | Description | |
|---|---|---|
![]() | AsParallel | Enables parallelization of a query. (Defined by ParallelEnumerable.) |
![]() | AsQueryable | Converts an IEnumerable to an IQueryable. (Defined by Queryable.) |
![]() | Cast<TResult> | Casts the elements of an IEnumerable to the specified type. (Defined by Enumerable.) |
![]() | OfType<TResult> | Filters the elements of an IEnumerable based on a specified type. (Defined by Enumerable.) |
| Name | Description | |
|---|---|---|
![]() ![]() | ICollection::IsSynchronized | Infrastructure. Gets a value indicating whether access to the collection is synchronized (thread safe). |
![]() ![]() | ICollection::SyncRoot | Infrastructure. Gets an object that can be used to synchronize access to the collection. |
![]() ![]() | IList::Add | Infrastructure. Adds an object to the end of the tree node collection. |
![]() ![]() | IList::Contains | Infrastructure. Determines whether the specified tree node is a member of the collection. |
![]() ![]() | IList::IndexOf | Infrastructure. Returns the index of the specified tree node in the collection. |
![]() ![]() | IList::Insert | Infrastructure. Inserts an existing tree node in the tree node collection at the specified location. |
![]() ![]() | IList::IsFixedSize | Infrastructure. Gets a value indicating whether the tree node collection has a fixed size. |
![]() ![]() | IList::Item | Infrastructure. Gets or sets the tree node at the specified index in the collection. |
![]() ![]() | IList::Remove | Infrastructure. Removes the specified tree node from the tree node collection. |
The Add, Remove, and RemoveAt methods enable you to add and remove individual tree nodes from the collection.
Note |
|---|
Enumerating the collection and removing nodes is not supported. |
You can also use the AddRange or Clear methods to add or remove all the tree nodes from the collection.
Classes cannot inherit from the TreeNodeCollection class.
The following code example displays customer information in a TreeView control. The root tree nodes display customer names, and the child tree nodes display the order numbers assigned to each customer. In this example, 1,000 customers are displayed with 15 orders each. 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. This example requires that you have a Customer object that can hold a collection of Order objects. It also requires that you have created an instance of a TreeView control on a Form.
// The basic Customer class. ref class Customer: public System::Object { private: String^ custName; protected: ArrayList^ custOrders; public: Customer( String^ customername ) { custName = ""; custOrders = gcnew ArrayList; this->custName = customername; } property String^ CustomerName { String^ get() { return this->custName; } void set( String^ value ) { this->custName = value; } } property ArrayList^ CustomerOrders { ArrayList^ get() { return this->custOrders; } } }; // End Customer class // The basic customer Order class. ref class Order: public System::Object { private: String^ ordID; public: Order( String^ orderid ) { ordID = ""; this->ordID = orderid; } property String^ OrderID { String^ get() { return this->ordID; } void set( String^ value ) { this->ordID = value; } } }; // End Order class void FillMyTreeView() { // Add customers to the ArrayList of Customer objects. for ( int x = 0; x < 1000; x++ ) { customerArray->Add( gcnew Customer( "Customer " + x ) ); } // Add orders to each Customer object in the ArrayList. IEnumerator^ myEnum = customerArray->GetEnumerator(); while ( myEnum->MoveNext() ) { Customer^ customer1 = safe_cast<Customer^>(myEnum->Current); for ( int y = 0; y < 15; y++ ) { customer1->CustomerOrders->Add( gcnew Order( "Order " + y ) ); } } // Display a wait cursor while the TreeNodes are being created. ::Cursor::Current = gcnew System::Windows::Forms::Cursor( "MyWait.cur" ); // Suppress repainting the TreeView until all the objects have been created. treeView1->BeginUpdate(); // Clear the TreeView each time the method is called. treeView1->Nodes->Clear(); // Add a root TreeNode for each Customer object in the ArrayList. myEnum = customerArray->GetEnumerator(); while ( myEnum->MoveNext() ) { Customer^ customer2 = safe_cast<Customer^>(myEnum->Current); treeView1->Nodes->Add( gcnew TreeNode( customer2->CustomerName ) ); // Add a child treenode for each Order object in the current Customer object. IEnumerator^ myEnum = customer2->CustomerOrders->GetEnumerator(); while ( myEnum->MoveNext() ) { Order^ order1 = safe_cast<Order^>(myEnum->Current); treeView1->Nodes[ customerArray->IndexOf( customer2 ) ]->Nodes->Add( gcnew TreeNode( customer2->CustomerName + "." + order1->OrderID ) ); } } // Reset the cursor to the default for all controls. ::Cursor::Current = Cursors::Default; // Begin repainting the TreeView. treeView1->EndUpdate(); }
Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2
The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.

