Thanks, I have tried implementing the event on dragstart in the source code which comes along with the control. Three files need changes, Treeview.htc, Treenode.cs and Treeview.cs. I have implemented the event but a new problem is coming. when we create the dll with original source code and add corresponding controls in toolbox and drag the treeview in the design view then .NET also creates a protected variable of corresponding treeview in code behind i.e. when we drag the treeview then an instance TreeView1 is created and a line "Protected WithEvents TreeView1 as Microsoft.Web.UI.Webcontrol.Treeview" is automatically added in .vb(code behind) file. But in case i create the dll with my code added then drag the treeview in the design then no line is added in codebehind. if i create the object with same name (TreeView1) in .vb file even then there is no link created with the design object. when we try to add a node in design mode and apply the changes, an error occurs displaying message "NullReferenceException: Object Reference is not set to instance of an object". Do you know any solution??? Also any other event like Expand and Collapse etc. does not seem to work I have written code for these events but events are not getting fiered. Kumar Saurabh Software Engneer Syndew Pvt Ltd New Delhi India
