js获取各搜索引擎的关键词

//方法
function GetQueryString() {    
    var refer = document.referrer;
    refer = refer + '&';
    var matches = '';   
    if(refer.match(/(www|m|youxuan).baidu/)){
        matches = refer.match(/W(wd|word)=(.*?)&/i);
        if(matches){
            matches = matches[2];
        }
    };
    if(refer.match(/m.sm.cn/)) {      
        matches = refer.match(/q=(.*?)&/i);
        if(matches) {
            matches = matches[1];
        }
    };
    if(refer.match(/sogou.com/)) {
        matches = refer.match(/keyword=(.*?)&/i);
        if(matches) {
            matches = matches[1];
        }
    };
   if(refer.match(/so.com/)) {
        matches = refer.match(/q=(.*?)&/i);
        if(matches) {
            matches = matches[1];
        }
    };
    if(matches && matches.indexOf("%") == 0) {
        matches = decodeURIComponent(matches);
    } else {
        matches = '';
    };

    return matches;
};

// 调用方法
var $wd=GetQueryString();
if($wd&&$wd.length>0){

}else{
    $wd=GetQueryString("word")
}

if($wd&&$wd.length>0){
    $wd=decodeURIComponent($wd);

    $line='关于【“'+$wd+'”】的问题,很荣幸为您解答疑问！';
}else{

    $line=' 您好，这里是......，请问有什么可以帮到您？';
}
$('#textFirst').html($line+"<span class="red">（咨询）</span>");