Hi Mike ,
Thanks for your interest in Syncfusion products.
To add data in second and third column in MultiColumnTreeView then you have to use the following code snippet.
[C#]
Syncfusion.Windows.Forms.Tools.MultiColumnTreeView.TreeNodeAdv treeNodeAdv2 = new Syncfusion.Windows.Forms.Tools.MultiColumnTreeView.TreeNodeAdv(new Syncfusion.Windows.Forms.Tools.MultiColumnTreeView.TreeNodeAdvSubItem[] {
treeNodeAdvSubItem4,
treeNodeAdvSubItem5,
treeNodeAdvSubItem6});
I have attached the sample for your reference.
http://websamples.syncfusion.com/samples/Tools.Windows/39321/main.htmPlease let me know if you are addressing something different.
Regards,
Nagaraj