this is object property, equals true for GanttTask; used to distinguish Project and Task in menu event handler.
ganttChartControl.attachEvent("onBeforeContextMenu", function(menu,obj) { if (obj.isProject) { // Project menu menu.setItemText("m1", "Project: " + obj.getName()); menu.setUserData("","obj",{type:"p",o:obj}); } else if (obj.isTask) { // Task menu menu.setItemText("m1", "Task: " + obj.getName()); menu.setUserData("","obj",{type:"t",o:obj}); } });