function do_something(){ let entries = d3.select(this) // "this" is a special keyword // Inside even callback functions, // it refers to the "context" of the event // i.e. the element that triggered the event. let is_unselected = entries.attr("fill") == "black" // circles start unselected with a stroke width of 0.4 entries.attr("fill", is_unselected ? "red" :"black") // If it is unselected (thin border), // then we select it (make it thicker) // and conversely. }

Je ne connaissais pas cet affichage. Très pratique. Je réutiliserai, merci!