C#递归遍历窗体所有textbox控件并设置textbox事件的方法

/// <summary>
///
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
public virtual void settextboxonenterstyle(object sender, eventargs e)
{
    if (sender is textbox)
    {
 textbox tbox = sender as textbox;
 if (!tbox.readonly)
 {
     tbox.backcolor = color.yellow;
 }
    }
}

/// <summary>
///
/// </summary>
/// <param name="sender"></param>
/// <param name="e"></param>
public virtual void settextboxonleavestyle(object sender, eventargs e)
{
    if (sender is textbox)
    {
 textbox tbox = sender as textbox;
 if (!tbox.readonly)
 {
     tbox.backcolor = color.white;
 }
    }
}
/// <summary>
///
/// </summary>
/// <param name="frm"></param>
public virtual void setformtextboxcontrolstyle(form frm)
{
    iteratecontrolssettextbox(frm.controls);
}

/// <summary>
///
/// </summary>
/// <param name="ctls"></param>
public virtual void iteratecontrolssettextbox(control.controlcollection ctls)
{
    foreach (control control in ctls)
    {
 if (control is textbox)
 {
     (control as textbox).enter += new eventhandler(settextboxonenterstyle);
     (control as textbox).leave += new eventhandler(settextboxonleavestyle);
 }

 if (control.controls.count > 0)
 {
     iteratecontrolssettextbox(control.controls);
 }
    }
}