javascript动画函数封装

Posted 2020-08-09

 function animate(obj, target) {
        clearInterval(obj.timer);
        obj.timer = setInterval(function () {
            var leader = obj.offsetLeft;
            var step = 10;//之前只能是正数 只能往右走
            /*if (leader < target) {
             step = step;
             } else {
             step = -step;
             }*/
            step = leader < target ? step : -step;
            //if (leader != target) {
            //Math.abs(target - leader) 当前位置到目标的距离
            //当前位置到目标的距离如果很大 这一步迈出之后 到不了目标 或者正好到
            // 就可以迈出这一步
            if (Math.abs(target - leader) >= Math.abs(step)) {
                leader = leader + step;
                obj.style.left = leader + "px";
            } else {
                //就差一点儿了手动放到目标即可
                obj.style.left = target + "px";
                clearInterval(obj.timer);
            }
        }, 15);
    }