private void buttonNextStep_Click(object sender, EventArgs e)
        {
            foreach (XmlNode node in issues.ChildNodes[1].SelectSingleNode("political_reforms"))
            {
                if (string.IsNullOrEmpty(countryHistory.ChildNodes[1].SelectSingleNode(node.Name).InnerText))
                {
                    MessageBox.Show("政治改革不能为空!");
                    return;
                }
            }
            countryHistory.Save(".\\xml\\history\\countries\\" + countryTagName + " - " + countryName + ".txt.xml");
            NewCountrySocialReforms ncsr = new NewCountrySocialReforms(countryTagName, countryName, mf);

            ncsr.Show();
            //ncsr.MdiParent = this.MdiParent;
            this.Close();
        }
        private void buttonPreviousStep_Click(object sender, EventArgs e)
        {
            NewCountrySocialReforms ncsr = new NewCountrySocialReforms(countryTagName, countryName, mf);

            foreach (XmlNode node in countryHistory.ChildNodes[1])
            {
                foreach (var techs in checkedListBoxTechnologies.Items)
                {
                    if (node.Name == techs.ToString())
                    {
                        countryHistory.ChildNodes[1].RemoveChild(node);
                    }
                }
            }
            ncsr.Show();
            this.Close();
        }