用js实现淡入淡出功能
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Title</title>
</head>
<body>
<div id="fade-obj" style="width:300px;height:300px;background:#000"></div>
<button id="fade-btn">淡出</button>
<script type="text/javascript">
var btn = document.getElementById('fade-btn');
var obj = document.getElementById('fade-obj');
// 透明属性
obj.style.opacity = 1;
// 淡出功能
function slideout() {
var opac = parseFloat(obj.style.opacity);
if (opac === 0) {
// 动画结束变成淡入
btn.display = false;
btn.innerHTML = '淡入';
// 在此点击就是淡出功能
btn.onclick = function () {
slideIn();
}
return true;
}
if (opac !== 0) {
opac = opac - 0.1;
// 动画过程中,按钮不能使用
btn.disabled = true;
}
obj.style.opacity = opac;
//利用setTimeout来展示动画
setTimeout(slideout, 50);
}
// 淡入功能
function slideIn() {
var opac = parseFloat(obj.style.opacity);
if (opac === 1) {
// 动画结束后变为淡出功能
btn.display = false;
btn.innerHTML = '淡出';
btn.onclick = function () {
slideout();
}
return true;
}
if (opac !== 1) {
opac = opac + 0.1;
// 动画过程中不准点击
btn.display = true;
}
obj.style.opacity = opac;
setTimeout(slideIn, 50);
}
btn.onclick = function () {
slideout();
}
</script>
</body>
</html>