ASP.NET TreeView and loading data on demand

Is there a way to force TreeView to load data on demand? In the other hand TreeView m开发者_运维技巧ust load data only when a node is to be expanded. TreeView is binded to a collection of data that is implementing IHierarchyData.

Three steps to do the trick:

1 - Set the TreeView.ExpandDepth to 0. This eliminates the expansion of the added TreeNode objects in the TreeView and shows the expansion symbol [+] next to each TreeNode that has the TreeNode.PopulateOnDemand property set to true.

2- Set the TreeNode.PopulateOnDemand to True for each branch TreeNode. When the TreeNode.ChildNodes collection is empty, the expansion symbol [+] will be showed only next to TreeNode objects that has TreeNode.PopulateOnDemand property set to true.

3- Handle the TreeView.TreeNodePopulate event to poulate branch nodes on expansion. This event will be fired when a TreeNode - with the TreeNode.PopulateOnDemand set to true - has been expanded right before the TreeView.TreeNodeExpanded event gets fired.

Or you can just populate your tree based on the different events available instead of loading your whole tree at once