The 4D command LISTBOX SELECT ROW can programaticalyl select a row in a listbox. The command takes in 2 required parameters, and an optional 3rd parameter. The 1st required parameter is the listbox object, and the 2nd required parameter is the listbox row. If 0 is passed in as the 2nd parameter, all rows in the listbox will be selected. The following code will select and highlight all the rows in the listbox: