GridView - How to specify a custom EditForm Template

This example illustrates how to:
- Specify a custom EditForm Template via the GridViewSettings.SetEditFormTemplateContent method;
- Define the UploadControl Extension inside this template for uploading files when creating/editing a row (Note that UploadControl should be wrapped with a form to be able to post a selected file);
- Edit the in-memory datasource.

See Also:
E3530: How to bind GridView with standard in-memory data sources (DataTable, List<T>)
E3983: GridView - How to edit in memory data source