<style>
body{margin: 0;}
ul{margin: 0;padding: 0;list-style: none;}
a{color:inherit;text-decoration: none;}
input{padding: 0;border: 0;}
.box{width: 340px;height: 38px;border: 2px solid gray;}
.con{overflow: hidden;}
.input{float: left;width: 300px;height: 38px;}
.search{width: 38px;height: 38px;float: right;background: url('http://sandbox.runjs.cn/uploads/rs/26/ddzmgynp/search.png') 0 -38px;}
.list{position: absolute;width: 298px;border: 1px solid #e6e8e9; overflow: hidden;}
.in{line-height: 30px;border-bottom: 1px solid lightblue;cursor:pointer;text-indent: 1em;}
.list .in:last-child{margin-bottom: -1px;}
.in:hover{background-color: #f9f9f9;}
</style>
<div class="box" id="box">
<div class="con">
<input class="input" id="search">
<a target="_blank" id="btn" href="javascript:;" class="search"></a>
</div>
<ul class="list" id="list"></ul>
</div>
<script>
function loadScript(url){
loadScript.mark = 'load';
var script = document.createElement("script");
script.type = "text/javascript";
script.src = url;
document.body.appendChild(script);
}
function callback(data){
if(data){
var arr = data.s;
var html = '';
for(var i = 0,len = arr.length; i < len; i++){
html+= "<li class='in'><a href='https://www.baidu.com/s?wd="+ arr[i]+"' target='_blank' style='display:block'>" + arr[i]+ "</a></li>"
}
list.innerHTML = html;
}
}
search.onkeyup = function(e){
e = e || event;
if(e.keyCode == '13'){
window.open('https://www.baidu.com/s?wd=' + this.value);
}
if(this.value){
if(search.data != this.value){
btn.setAttribute('href','https://www.baidu.com/s?wd=' + this.value);
var that = this;
loadScript("https://sp0.baidu.com/5a1Fazu8AA54nxGko9WTAnF6hhy/su?wd=" + that.value + "&&cb=callback");
}
}else{
list.innerHTML = '';
}
search.data = this.value;
console.log( search.data ,this.value)
}
search.onclick = function(e){
e = e || event;
list.style.display = 'block';
if(e.stopPropagation){
e.stopPropagation();
}else{
e.cancelBubble = true;
}
}
document.onclick = function(){
list.style.display = 'none';
}
</script>