菜鸟备忘

    function changeImage() {
        var img = document.getElementById("myImg");
        if (img.src.match("1"))
            img.src = "img/2.jpg";
        else
            img.src = "img/1.jpg";
    }

    function isArray(myArray)
    {
        console.log(myArray.constructor.toString());
        return myArray.constructor.toString().indexOf("Array") > -1;
    }