I have a simple implimentation of a WebExcelExporter that exports data in a WebHierarchicalDataGrid.
It is a simple task list with values such as TaskTitle, TaskOwner, TaskStatus, & TaskDueDate.
When sorting using a column that does not contain any nulls, everything works fine.
If sorting with a column that contains some nulls, you get the following result:
Object reference not set to an instance of an object.
on this line of code:
this.WebExcelExporter1.Export(this.WebHierarchicalDataGrid1, wSheet);

If, for example, I am sorting by TaskStatus and some of the tasks do not have a value, the WebHierarchicalDataGrid knows how to handle this.... it creates a "group" that has a label something like this: "TaskStatus: (%number%)".
The TaskStatus groups that have a value for TaskStatus get a label something like this: "TaskStatus: Active (%number%)", or "TaskStatus: Pending (%number%)", etc...

when you click export, you get the "Object reference not set to an instance of an object." error.

Evidently, the WebHierarchicalDataGrid knows how to show all rows of data, creating a group for those rows that have a null value, but the exported doesn't know how to write them to an XLS?
Can the exporter not be programmed to create a group in the XLS like "TaskStatus: (%number%)"?