我正在运行这段代码。
ScriptEngine engine = new ScriptEngineManager().getEngineByName("nashorn");
engine.eval("var out;");
engine.eval("var out1 = null;");
Object m = engine.get("out");
Object m1 = engine.get("out1");
获取m == null和m1 == null。
如何确定值是未定义还是空?
engine.eval("out === undefined")
返回什么? - chrylis -cautiouslyoptimistic-