GridView动态绑定事件及判断数据所在行

在GridView的RowDataBound事件时触发：
protected void gvCity_RowDataBound(object sender, GridViewRowEventArgs e)
        {

            if (e.Row.RowType == DataControlRowType.DataRow)
            {
                ImageButton ib = (ImageButton)e.Row.FindControl("imgbtneditor");
                string id = ib.CommandArgument.ToString();
                ib.Attributes.Add("onclick", "update('update','" + id + "')");
               
            }
        }

判断数据所在行

 protected void btnChange_Click(object sender, EventArgs e)
  {
                    
                    Button btn=(Button)sender;//转换成sender
                    string summaryNid = btn.CommandArgument.ToString();
                   //获得控件所在GridView所在行数
 int index = (btn.NamingContainer as GridViewRow).RowIndex;
                    DropDownList ddlHeadTeacher = (DropDownList)gvApply.Rows[index].FindControl("ddlHeadTeacher");
               
}