父窗体、子窗体关系设置

父窗体内函数：

/// <summary>
  /// 电台频率框获取焦点后 弹出数字窗口
  /// </summary>
  /// <param name="sender"></param>
  /// <param name="e"></param>
  private void txtFrequency_Enter(object sender, EventArgs e)
  {
   DigitDialog fsDigit = new DigitDialog();
   this.AddOwnedForm(fsDigit);//添加这句

fsDigit.Show();
  }

子窗体内函数：

private void btnNum0_Click(object sender, EventArgs e)
  {
   Button btnNumber = sender as Button;
   Form fParent = (Form)this.Owner;//获取父窗口
   if (null != fParent)
   {
    foreach (Control crtl in fParent.Controls)
    {

//添加代码

}

}

}

父窗体、子窗体关系设置