thinkphp不填关键词不展示

thinkphp搜索这里不填写关键词搜索，显示出所有列表出来
下面这个程序要怎么更改才能不填关键词不显示列表出来

<form action="/?m=search" method="post">
            <input type="hidden" name="modelid" value="9" id="modelid2">
            <input type="text" class="chunk" name="keyword" placeholder="请输入您要查询的条件" />
            <button type="submit" class="" value="" target="menuFrame" />点击查询</button>
</form>

<?php
 
class SearchAction extends PublicAction
{
 
    public function index()
    {
        $keyword = $_GET['keyword'] = I('keyword');
        $modelid = $_GET['modelid'] = I('modelid', 9, 'intval');
 
        $this->assign(I('request.'));
        
        //可搜索内容模型
        $model_search = array();
        foreach ($this->Model as $val) {
            if ($val['issearch'] == 1) {
                $model_search[] = $val;
            }
        }
        $this->assign('model_search', $model_search);
 
        $this->assign('seo_title', $this->Config['seo_title']);
        $this->assign('seo_keywords', $this->Config['seo_keywords']);
        $this->assign('seo_description', $this->Config['seo_description']);
 
        $modelname = $this->Model[$modelid]['tablename'];
 
        $where = array();
        $where['status'] = 1;
        $where['lang'] = LANG_ID;
 
        $where['title'] = array('like',"%$keyword%");
 
        $db = M($modelname);
        $count = $db->where($where)->count();
        
        if($count) {
            import("@.ORG.Page");
            $page = new Page($count, 6);
            $pages = $page->show();
            
            $field = 'id,url,title,keywords,description,thumb,createtime,tel';
 
            $list = $db->field($field)->where($where)->order('listorder desc,id desc')->limit($page->firstRow . ',' . $page->listRows)->select();
 
            $this->assign('pages', $pages);
            $this->assign('list', $list);
        }
        
        fangke_log('search','index',0,$keyword);
        
        $this->assign(I('get.'));
        $this->display();
    }
}

where 条件 里默认拼接一下 where 1=1 就好了。有输入关键字时根据关键字匹配输出，没有输入时全部输出。

只要把
  
        $where['title'] = array('like',"%$keyword%");
        $db = M($modelname);
        $count = $db->where($where)->count();
改成
$count=0;
if($keyword!=''){
  $where['title'] = array('like',"%$keyword%");
  $db = M($modelname);
   $count = $db->where($where)->count();
}

这样的话，你不输入关键词，就不会显示列表数据了