C# .NET - Trre List View

Each item in a tree-view control can have four bitmapped images associated with it.

• An image, such as an open folder, displayed when the item is selected.
• An image, such as a closed folder, displayed when the item is not selected.
• An overlay image that is drawn transparently over the selected or nonselected image.
• A state image, which is an additional image displayed to the left of the selected or nonselected image. You can use state images, such as checked and cleared check boxes, to indicate application-defined item states.

By default, a tree-view control does not display item images. To display item images, you must create image lists and associate them with the control. For more information about image lists, see http://msdn.microsoft.com/en-us/library/windows/desktop/bb761389%28v=vs.85%29.aspx.





http://www.mobzystems.com/code/transparent-state-images-in-tree-views/
http://msdn.microsoft.com/en-us/library/windows/desktop/bb760017%28v=vs.85%29.aspx#tv_image_lists

Yes, you can display like this-

private void FillTreeView()
{
	// Load the images in an ImageList.
	ImageList myImageList = new 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 = new 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.
	foreach(Customer myCustomer in customerArray)
	{
		// Add a child tree node for each Order object.
		int countIndex=0;
		TreeNode[] myTreeNodeArray = new TreeNode[myCustomer.CustomerOrders.Count];
		foreach(Order myOrder in myCustomer.CustomerOrders)
		{
			// Add the Order tree node to the array.
			myTreeNodeArray[countIndex] = new TreeNode(myOrder.OrderID,
			  unselectedOrderImageIndex, selectedOrderImageIndex);
			countIndex++;
		}
		// Add the Customer tree node.
		TreeNode customerNode = new TreeNode(myCustomer.CustomerName,
			unselectedCustomerImageIndex, selectedCustomerImageIndex, myTreeNodeArray);
		myTreeView.Nodes[0].Nodes.Add(customerNode);
	}
}

You can use images to indicate an expandable node, a collapsible node, or a node that does not expand or collapse. You can create images for this purpose in most graphics programs.

To assign an image to a particular node type, you assign the location of the image file to be used to the corresponding property. These properties include http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.treeview.expandimageurl.aspx, http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.treeview.collapseimageurl.aspx, and http://msdn.microsoft.com/en-us/library/system.web.ui.webcontrols.treeview.noexpandimageurl.aspx. The following example sets these properties to custom images in the Images directory of the Web site.

    <asp:TreeView ID="TreeView1" 
        runat="server" 
        DataSourceID="XmlDataSource1"
            ExpandImageUrl="~/Images/ExpandAll.gif"
            CollapseImageUrl="~/Images/CollapseAll.gif"
            NoExpandImageUrl="~/Images/stop.gif">
    </asp:TreeView>