abstract：<!DOCTYPE html><html><head> <meta charset="utf-8"> <title>微博输入</title> <style type="text/css"> b
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>微博输入</title>
<style type="text/css">
body{font-size: 12px;}
.box{width: 600px;height: 160px;border:10px solid pink; margin: 0px auto;padding:10px; }
img{float: left;}
.box1{float: left;margin-left: 255px;width: 150px;height: 24px;text-align: right;font-size: 14px;color: #888;}
.box1 span{font-size: 16px;font-weight: bold;}
#text{width:600px;height: 100px;border: 1px solid #ccc;margin-top: 5px;}
.box #sp1,#sp2,#sp3,#sp4,#sp5,#sp6{float: left;width: 30px;height: 32px;line-height: 32px;padding-left: 26px;}
#sp1{background: url(images/an5.png) no-repeat left center;}
#sp2{background: url(images/an4.png) no-repeat left center;}
#sp3{background: url(images/an3.png) no-repeat left center;}
#sp4{background: url(images/an2.png) no-repeat left center;}
#sp5{background: url(images/an1.png) no-repeat left center;width: 40px;}
#sp6{ margin-left: 158px;margin-right:15px;color: #888; }
#bt{float: left;width: 80px;height: 30px;border: none;background: #ffc09f;color: #fff;border-radius: 5px;}
#bt:hover{color: chocolate}
</style>
<script type="text/javascript">
var text,number,m;
window.onload=function (){
text = document.getElementById('text');
number = document.getElementById('number');
bt = document.getElementById('bt');
text.oninput=function aa(){
m=25-text.value.length;//微博限制字数是140
if(m<0){
number.style.color="red";
bt.disabled = true;
bt.style.backgroundColor = 'red';
alert("字数太多，不可以发布");
text.focus();
}
else{
number.style.color="#888";
bt.disabled = false;
bt.style.backgroundColor = 'green';
}
number.innerHTML=m;
};
// text.addEventListener('input',getText,false);
bt.onclick=function(){
if (m === 25) {
alert("你还没有输入");
text.focus()
}else{
alert("发布成功");
text.value = '';
}
};
aa()
}
</script>
</head>
<body>
<div class="box">
<img src="images/12.png">
<div class="box1">还可以输入<span id="number"></span>字</div>
<textarea id="text"></textarea>
<span id="sp1">表情</span>
<span id="sp2">图片</span>
<span id="sp3">视频</span>
<span id="sp4">话题</span>
<span id="sp5">长微博</span>
<span id="sp6">公开</span>
<input type="button" value="发布" id="bt" disabled>
</div>
</body>
</html>
Correcting teacher：天蓬老师Correction time：2019-05-28 16:50:13
Teacher's summary：js是基于事件驱动的, 特别是事件循环机制, 不至于出现阻塞