为什么上节讲的时候可以timer = setInterval(autoPlay(), 2000);这样写,而我这样写就只能执行一次,就是1秒后没不执行了
<!doctype html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title>Document</title>
<script type="text/javascript">
window.onload=function(){
var send=document.getElementById('send'),
second=document.getElementById('second'),
times=5,
timer=null;
send.onclick = function () {
// 计时开始
timer = setInterval(function () {
autoPlay();
}, 1000)
}
//自动播放
function autoPlay(){
if (times <= 0){
times = 5;
send.disabled=false;
send.value = '发送验证码';
second.innerHTML=0;
clearInterval(timer)
return;
}
send.disabled=true;
send.value = '正在发送...';
second.innerHTML=times;
times--;
}
}
</script>
</head>
<body>
<input type="button" id="send" value="发送验证码"><button disabled><span id="second">0</span>秒后重试</button>
</body>
</html>为什么现在只能写在function内了
