datalist结合objectdatasource的代码问题

//点击更新按钮
protected void DataList1_UpdateCommand(object source, DataListCommandEventArgs e)
    {
job = new Model.Job_Model();
        job.Job_id = 1;
        job.Job_desc = "desc";
        job.Min_lvl = 20;
        job.Max_lvl = 200;
ObjectDataSource1.Update();
}
//objectdatasource的事件
    protected void ObjectDataSource1_Updating(object sender, ObjectDataSourceMethodEventArgs e)
    {
//代码怎么写？
}
//BLL层需要调用的方法
public bool Update_BLL(Model.Job_Model job)
        {
            jobdal = new DAL.Job_DAL();
            return jobdal.Update_Job_Dal(job);
        }

中间那个代码怎么写 ？怎么吧job对象加到objectdatasource的更新参数里边。