只需要在wk.js里把这个uploadExcel里的onUploadSuccess修改下就行了

'onUploadSuccess': function(file, data, response) {
                if(data.code == 200){
                    wk.success('导入成功!',excel_url);
                }else{
                    layer.msg(data.msg,{icon:2,time:2000,shade:0.1},function(index){
                        location.reload()
                    });
                }
            },

返回

return json(['code'=>0,'msg'=> '无此分类']);
or
return json(['code'=>200]);