小白求助 JSB绑定以后,在JS调用还是显示没有调用

cocos creator版本是2.4.0

编译运行以后 就报以下错误

[ERROR] (…\cocos\scripting\js-bindings\jswrapper\v8\Object.cpp, 574): Invoking function (10D8B4A8) failed!
E/jswrapper (274): ERROR: Uncaught TypeError: cc.jsbTest is not a constructor, location: src/cocos2d-jsb.04c94.js:0:0