C1Splitter supports templating , which you can use to make a nested splitter.

In order to make the nested sample, the following properties and events are used in this sample.

• ContentTemplate
• FullSplit
• Orientation
• OnClientExpanded
• OnClientCollapsed
• OnClientSized

This sample uses the ContentTemplate to nest the hsplitter in the vsplitter. Here, the FullSplit property is used to fill the vsplitter's whole panel2 and with the OnClientExpanded/OnClientCollapsed/OnClientSized events the nested splitter(hsplitter) can be refreshed after the vsplitter is resized(expanded/collapsed/sized).