Expanding and Collapsing Detail Rows
To access detail data, an end-user must expand a data row by clicking on its expand button.
By default, end-users can expand several master rows simultaneously. This behavior is controlled by the ASPxGridViewDetailSettings.AllowOnlyOneMasterRowExpanded option. If this option is enabled, only one detail row can be displayed at a time.
To display and/or hide detail data in code, use the ASPxGridView.DetailRows property. This property returns the WebDataDetailRows object, whose methods allow you to expand/collapse individual detail rows and all rows simultaneously, obtain the number of visible detail rows, etc.
ASPxGridView provides multiple client methods that allow you to expand and/or collapse detail rows on the client.
Expanding/Collapsing Individual Detail Rows
Expanding/Collapsing All Detail Rows
Each time a detail row is expanded or collapsed, the ASPxGridView.DetailsChanged event is raised.