The ListView.ItemActivate event occurs when the user activates one or more items in the System.Windows.Forms.ListView control. The user can activate an item with either a single-click or double-click, depending on the value of the ListView.Activation property, or with the keyboard. From within the event handler for the ListView.ItemActivate event, you can reference the ListView.SelectedItems or ListView.SelectedIndices properties to access the collection of items selected in the System.Windows.Forms.ListView to determine which items are being activated.
For more information about handling events, see Consuming Events.