js 获取上一页所带的百度关键词

<div class="fswt">
  <textarea type="text" id="fswt_nr" class="fl" placeholder="请输入您的问题" name="text"></textarea>
  <img id="dyfs" class="fl" src="./static/images/send.gif" />

</div>
  
  
  
<script language="javascript">


    var url = window.location.href;//当前页面
    var shang=window.document.referrer; //来源上一页    
    var biaos=encodeURIComponent("自设入口");//标识
    
    if(shang.indexOf("word")!=-1){
        
        var k = window.document.referrer.split('word=')[1].split('&')[0];
        /*将关键词赋值给input*/ 
        document.getElementById("fswt_nr").value=decodeURIComponent(k);
        
                
        }else{
        
            }
            
       /*进入页面后5秒跳转快商通*/    
        /*
        setTimeout("zjtiao()",5000);
            
        function zjtiao(){    
            var dyfs=document.getElementById("fswt_nr").value;
            KS.openChatWin({cv:dyfs,sText:'自设入口'});            
        }
        */

  setTimeout("dh1()",2000);
    function dh1(){
        document.getElementById("hd1").style.visibility="visible";
        setTimeout("dh2()",3000);
    }
    function dh2(){
        document.getElementById("hd2").style.visibility="visible";
    }

    var index=0;
    var str=document.getElementById("fswt_nr").placeholder;
    function type(){
    if(index==str.length+1){
        index=0;
    }
    document.getElementById("fswt_nr").placeholder = str.substring(0,index++);
    }
    setInterval(type, 500);
    
    
    document.getElementById("dyfs").onclick=function(){
        var dyfs=document.getElementById("fswt_nr").value;
          KS.openChatWin({cv:dyfs,sText:'自设入口'});
        }
</script>