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Query: Keep getting Null Reference when exporting grid to Excel
We are able to reproduce the reported issue in the shared sample, and after validating the sample we could see that you have exported the Grid with dataSource in form of dictionary object instead of list of objects. DataSource for the Grid can be in form of list of objects / dataTable etc. but not dictionary object. So to export the Grid kindly serialize the dictionary object to model class and export it in form of list of objects / datatable.
Or if you want to export without model class then kindly use TypeBuilder concept. Refer the below knowledge base documentation to export the Grid using TypeBuilder.
If you are facing any issue while applying above solution, please get back to us with more details.