js 数组的forEach 函数

        var numbers = [4, 9, 16, 25];

        function myFunction(item, index) {
            console.log("item:" + item + "__index:" + index);
        }
        numbers.forEach(myFunction);
        console.log("_________________");
        for (var i = 0; i < numbers.length; i++) {
            console.log("item:" + numbers[i] + "__index:" + i);
        }