<!DOCTYPE html> <html dir="ltr"> <head> <meta charset="utf-8"> <title>微博</title> <style media="screen"> .b1{width:600px;height:160px;border:10px solid pink;margin:0px auto;padding:10px;} img{float:left;} #text{width:600px;height:100px;border:1px solid #888;margin-top:5px;} .b2{float:right;font-size:14px;color:#888;margin-right:5px;} span{font-size:13px;} #s1,#s2,#s3,#s4,#s5,#s6{float: left;width: 30px;height: 32px;line-height: 32px;padding-left: 26px;} #s1{background: url(images/an5.png) no-repeat left center;} #s2{background: url(images/an4.png) no-repeat left center;} #s3{background: url(images/an3.png) no-repeat left center;} #s4{background: url(images/an2.png) no-repeat left center;} #s5{background: url(images/an1.png) no-repeat left center;width: 40px;} #s6{ margin-left: 158px;margin-right:15px;color: #888; } #fb{width: 80px;height: 30px;border: none;background: #ffc09f;color: #fff;border-radius: 5px;} #num{font-size:16px;font-weight:bold;} </style> </head> <body> <div> <img src="./images/12.png" alt=""> <div> 还可以输入<span id="num"></span>字 </div> <textarea id="text"></textarea> <span id="s1">表情</span> <span id="s2">图片</span> <span id="s3">视频</span> <span id="s4">话题</span> <span id="s5">长微博</span> <span id="s6">公开</span> <input type="button" id="fb" onclick="cc()" value="发布"> </div> </body> <script type="text/javascript"> var text,num,m; window.onload=function(){ text=document.getElementById('text'); num=document.getElementById('num'); text.onkeyup=function aa(){ m=140-text.value.length; if(m<0){ num.style.color="red"; }else{ num.style.color="#888"; } num.innerHTML=m; } } function cc(){ if(m==140){ alert("你还没有输入"); }else if(m<0){ alert("字数太多,发布失败"); }else{ alert("发布成功"); } } </script> </html>