TreeNode::ImageIndex Property


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Gets or sets the image list index value of the image displayed when the tree node is in the unselected state.

Namespace:   System.Windows.Forms
Assembly:  System.Windows.Forms (in System.Windows.Forms.dll)

property int ImageIndex {
	int get();
	void set(int value);

Property Value

Type: System::Int32

A zero-based index value that represents the image position in the assigned ImageList.

The ImageIndex value is the index value of an Image stored in the ImageList assigned to the TreeView::ImageList property.


The default value of the ImageIndex property is the same as the ImageIndex property of the TreeView control that the TreeNode is assigned to.

The ImageKey and ImageIndex properties are mutually exclusive; therefore, if one property is set, the other is ignored. If you set the ImageKey property, the ImageIndex property is automatically set to -1. Alternatively, if you set ImageIndex, ImageKey is automatically set to an empty string ("").

The following code example creates and assigns an ImageList to a TreeView control and fills the TreeView control with TreeNode objects. The tree nodes are assigned images from the ImageList that is displayed when the tree node is in a selected or unselected state. This example requires that you have a Form that contains a TreeView, and an ArrayList that contains Customer objects that each contain Order objects. It also requires that the Customer and Order objects are defined.

ref class Customer
   ArrayList^ CustomerOrders;
   String^ CustomerName;
   Customer( String^ myName )
      CustomerName = myName;
      CustomerOrders = gcnew ArrayList;


ref class Order
   String^ OrderID;
   Order( String^ myOrderID )
      this->OrderID = myOrderID;


   void FillTreeView()

      // Load the images in an ImageList.
      ImageList^ myImageList = gcnew ImageList;
      myImageList->Images->Add( Image::FromFile( "Default.gif" ) );
      myImageList->Images->Add( Image::FromFile( "SelectedDefault.gif" ) );
      myImageList->Images->Add( Image::FromFile( "Root.gif" ) );
      myImageList->Images->Add( Image::FromFile( "UnselectedCustomer.gif" ) );
      myImageList->Images->Add( Image::FromFile( "SelectedCustomer.gif" ) );
      myImageList->Images->Add( Image::FromFile( "UnselectedOrder.gif" ) );
      myImageList->Images->Add( Image::FromFile( "SelectedOrder.gif" ) );

      // Assign the ImageList to the TreeView.
      myTreeView->ImageList = myImageList;

      // Set the TreeView control's default image and selected image indexes.
      myTreeView->ImageIndex = 0;
      myTreeView->SelectedImageIndex = 1;

      /* Set the index of image from the
        ImageList for selected and unselected tree nodes.*/
      this->rootImageIndex = 2;
      this->selectedCustomerImageIndex = 3;
      this->unselectedCustomerImageIndex = 4;
      this->selectedOrderImageIndex = 5;
      this->unselectedOrderImageIndex = 6;

      // Create the root tree node.
      TreeNode^ rootNode = gcnew TreeNode( "CustomerList" );
      rootNode->ImageIndex = rootImageIndex;
      rootNode->SelectedImageIndex = rootImageIndex;

      // Add a main root tree node.
      myTreeView->Nodes->Add( rootNode );

      // Add a root tree node for each Customer object in the ArrayList.
      IEnumerator^ myEnum = customerArray->GetEnumerator();
      while ( myEnum->MoveNext() )
         Customer^ myCustomer = safe_cast<Customer^>(myEnum->Current);

         // Add a child tree node for each Order object.
         int countIndex = 0;
         array<TreeNode^>^myTreeNodeArray = gcnew array<TreeNode^>(myCustomer->CustomerOrders->Count);
         IEnumerator^ myEnum = myCustomer->CustomerOrders->GetEnumerator();
         while ( myEnum->MoveNext() )
            Order^ myOrder = safe_cast<Order^>(myEnum->Current);

            // Add the Order tree node to the array.
            myTreeNodeArray[ countIndex ] = gcnew TreeNode( myOrder->OrderID,unselectedOrderImageIndex,selectedOrderImageIndex );
         TreeNode^ customerNode = gcnew TreeNode( myCustomer->CustomerName,unselectedCustomerImageIndex,selectedCustomerImageIndex,myTreeNodeArray );
         myTreeView->Nodes[ 0 ]->Nodes->Add( customerNode );

.NET Framework
Available since 1.1
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