In the current release of WebGrid there is some feature which has not been supported and unfortunately HierarchicalGrid in ClientBinding is one of them. This feature is planned for future release of WebGrid.

Quoting from the WebGrid whitepaper:

The following features are not supported in version 7, although the architecture has been properly designed to support implementation for those features in the next version:

• Hierarchical Grid (Child Tables)
• Self Referencing

 

The full feature and limitations of WebGrid client binding feature could be read in WebGrid Whitepaper under the subtitle Supported Features and Limitations

Hello Scott,

The Client Binding in v7 is strongly focused on flat table with support on all existing databound features such as sorting, grouping, filtering, and so on -- as well as data service support in native JSON format.

As Glenn pointed out, the hierarchical tables are unsupported in this version. We'll support hierarchical tables and more features in the next version.

Let me know if you have other questions, or feedback. Thanks!