ASP.Net中GridView多层嵌套，用最里层的控件获取到外层GridView

protected void ddlCode_SelectedIndexChanged(object sender, EventArgs e)
{    
    DropDownList ddlCode = (DropDownList)sender;
    //根据现有的控件的NamingContainer获取到该控件所在的父级GridView的所在行
    GridViewRow gvr = (GridViewRow)ddlCode.NamingContainer;
 //根据获得的gvr使用同样的属性获得外层的GridView
    GridView gv = gvr.NamingContainer as GridView;
//获取gvr的行索引
int i_RowIndex = gvr.RowIndex;

}