Javascript/.prototype

解説 原型となるオブジェクトを生成
sample1
sample1code
function s1Func(){}
s1Func.prototype.spring = function() {
  console.log('春');
};
var s1Btn = document.getElementById("s1Btn");
var tutuji = new s1Func();
s1Btn.addEventListener("click", tutuji.spring);