Click the "right" button, the red #red block buffer start right movement, arrived in a black vertical position to stop automatically, click on the "right" #red will no longer block the movement again. Click the "left" button, the red #red block buffer leftward movement, arrived to blue vertical position stops automatically, click again "left" #red block will no longer sport.
<!DOCTYPE html>
<html lang="zh-CN">
<head>
<meta charset="UTF-8">
<title>JS小案例：缓冲运动</title>
<style>
#red {
width: 200px;
height: 200px;
background: red;
position: absolute;
top: 50px;
left: 200px;
}
.black {
position: absolute;
width: 1px;
height: 200px;
left: 900px;
background: black;
top: 50px;
}
.blue {
position: absolute;
width: 1px;
height: 200px;
left: 200px;
background: blue;
top: 50px;
}
</style>
<script>
//补充代码
</script>
</head>
<body>
<input type='button' value='向右' id='btn' />
<input type='button' value='向左' id='btn-left' />
<div id='red'></div>
<div class='black'></div>
<div class='blue'></div>
</body>
</html>
Reference Code:
window.onload = function () {
var oDiv = document.getElementById('red');
var oBtn = document.getElementById('btn');
var oBtnLeft = document.getElementById('btn-left');
var timer = null;
function startMove(iTarget) {
clearInterval(timer);
timer = setInterval(function () {
var speed = (iTarget - oDiv.offsetLeft) / 30;
speed=speed>0?Math.ceil(speed):Math.floor(speed);
if (oDiv.offsetLeft == iTarget) {
clearInterval(timer)
} else {
oDiv.style.left = oDiv.offsetLeft + speed + 'px';
}
}, 30)
}
oBtn.onclick = function () {
startMove(700);
}
oBtnLeft.onclick = function () {
startMove(200);
}
}