In Asp.net 2.0, the selectedvalue of the Treeview control cannot be obtained.

These days CodeIn some cases, the selectedvalue of the Treeview control is obtained in the background code of the page, and the obtained value is always null, however, the data source control that is directly bound to the selectedvalue of the Treeview control can work normally.
Cause:
The Treeview control has a value only when its selectedvalue is changed and is returned to the server. In subsequent refreshes, The selectedvalue of the Treeview control does not have a value.
To solve this problem, I used to add a hidden control to the page. When the selectedvalue OF THE Treeview control changes, it is uploaded back to the server, that is, in the corresponding function of the onadaptedselectednodechanged event of the Treeview control, the selectedvalue of the Treeview control is written to the hidden control. In the future, the selectedvalue of the Treeview control will be retrieved from the hidden control, in this case, OK.