<a class = "x" id="{$photo.id}" uid="{$Think.session.uid}" status = "{$collect_pic}" href = "javascript:void(0);">
<if condition = "$collect_num gt 0">
  <span>取消收藏</span>
<else/><span>收藏</span></if></a>

//点击收藏，实现已收藏
  $('.x').on('click',function(){
    var Oa=$(this);
    var id=Oa.attr('id');//获取图片id属性
    var uid = Oa.attr('uid');//获取用户id
    var status = Oa.attr('status'); //获取收藏状态 1收藏，0取消收藏
    $.post('url',{id:id,uid:uid,status:status},function(msg){
      if(msg.status==1){
        Oa.find("span").text('取消收藏');
        Oa.attr('status','1');
      }else{
        Oa.find("span").text('收藏');
        Oa.attr('status','0');
      }
    },'json')
  })

//判断用户是否已收藏该图片
      $data['uid'] = $_SESSION['uid'];
      $data['pid'] = $pid;
      $collect_pic = M('collect')->where($data)->getfield('status');
      $this->collect_num = $collect_num;
      $this->collect_pic = $collect_pic;

//收藏成功
    public function cang(){

      $data['pid'] = isset($_POST['id'])"ok";
          $msg['status'] = 1;
          $this->ajaxreturn($msg);
          exit;        
        }else{
          $msg['info'] = 'fail';
          $msg['status'] = 1;
          $this->ajaxreturn($msg);
        }
      }else{
        //取消收藏
        if($db->where($data)->delete()){
          $msg['info'] = "ok";
          $msg['status'] = 0;
          $this->ajaxreturn($msg);
          exit;
        }else{
          $msg['info'] = 'fail';
          $msg['status'] = 0;
          $this->ajaxreturn($msg);
        }
      }