[ 
 {"id":1,"initial":"ad","keyword":"奥迪"}, 
 {"id":2,"initial":"ada4l","keyword":"奥迪A4L"}, 
 {"id":3,"initial":"ada6l","keyword":"奥迪A6L"}, 
 {"id":4,"initial":"adq5","keyword":"奥迪Q5"}, 
 {"id":5,"initial":"ada3","keyword":"奥迪A3"}, 
 {"id":6,"initial":"adq7","keyword":"奥迪Q7(进口)"}, 
 {"id":7,"initial":"ada8","keyword":"奥迪A8L(进口)"}, 
 {"id":8,"initial":"bm","keyword":"宝马"}, 
 {"id":9,"initial":"bm5x","keyword":"宝马5系"}, 
 {"id":10,"initial":"bm7x","keyword":"宝马7系"}, 
 {"id":11,"initial":"bt","keyword":"本田"}, 
 {"id":12,"initial":"bqsbx25","keyword":"北汽绅宝 X25"}, 
 {"id":13,"initial":"bqsbx35","keyword":"北汽绅宝X35"}, 
 {"id":14,"initial":"bqsbx55","keyword":"北汽绅宝X55"} 
] 

<form class="fl search_form" action="#" method="post"> 
 <input class="search_text" id="searchKey" type="search" placeholder="请输入搜索关键字" onkeyup="searchSuggest(this);"/> 
 <input class="search_btn" type="submit" value="搜索"/> 
</form> 
<!--start--智能搜索关键字匹配弹出层--> 
<ul class="keywords_list"></ul> 
<!--end--智能搜索关键字匹配弹出层--> 

//当在搜索框输入内容时，根据关键字匹配，显示弹出层 
function searchSuggest(obj){ 
 var searchKey=$(obj).val(); 
 var reg = new RegExp(searchKey,"i"); //忽略大小写匹配搜索框中输入的内容 
 $.ajax({ 
 type:"get", 
 url:"data/keyword.json", 
 dataType:"json", 
 success:function(data){ 
  var arr=[]; 
  for(var i=0,len=data.length;i<len;i++){ 
  if(searchKey!="" && (data[i].initial.search(reg)!=-1 || data[i].keyword.search(reg)!=-1)) { 
   arr.push("<li onclick='changeSearchKey(this);'>"+data[i].keyword+"</li>"); 
  } 
  }     
  $(".keywords_list").html(arr).show(); 
 } 
 }); 
} 
//单击匹配列表中的关键字选项时，将该关键字显示在搜索框中 
function changeSearchKey(obj){ 
 var value=$(obj).text(); 
 $("#searchKey").val(value); 
 $('.keywords_list').hide(); 
}