静态用户名和密码的登录练习

 private void button2_Click(object sender, EventArgs e)

 {

 textUser.Text = Convert.ToString(textUser.Text);

 textBox2.Text = textBox2.Text.ToString();

 if (textUser.Text == "admin" && textBox2.Text == "")

 {

 MessageBox.Show("登录成功");

 }

 else

 {

 MessageBox.Show("用户名或密码错误");

 }

 }

 窗体关闭消息提示的练习

 private void Form2_FormClosing(object sender, FormClosingEventArgs e)

 {

 DialogResult re = MessageBox.Show("确定关闭？","消息",MessageBoxButtons.YesNo);//是否关闭消息提示框

 if (re == DialogResult.No)

 {

 e.Cancel = true; //关闭

 }

 else

 {

 e.Cancel = false; //不关闭

 }

 }