示例#1
0
        private void button2_Click(object sender, EventArgs e)
        {
            注册 form2 = new 注册();

            form2.Show();
            this.Hide();
        }
示例#2
0
        private void button1_Click(object sender, EventArgs e)
        {
            String userid, password;

            userid   = textBox1.Text;
            password = textBox2.Text;
            String        ConnstrWindows = @"Data Source=LAPTOP-6HF7DH62;Initial Catalog=Demo;Integrated Security=True";
            SqlConnection SqlCon         = new SqlConnection(ConnstrWindows);

            SqlCon.Open(); //打开数据库
            String        Sql           = "select userid,password from [user] where userid='" + userid + "' and password='******'";
            SqlCommand    sqlCommand    = new SqlCommand(Sql, SqlCon);
            SqlDataReader sqlDataReader = sqlCommand.ExecuteReader();

            if (sqlDataReader.HasRows)
            {
                Form3 form3 = new Form3();
                form3.Show();
                this.Hide();
            }
            else
            {
                DialogResult dr = MessageBox.Show("是否注册新用户?", "登录失败", MessageBoxButtons.YesNo, MessageBoxIcon.Question);
                if (dr == DialogResult.Yes)
                {
                    注册 form2 = new 注册();
                    form2.Show();
                    this.Hide();
                }
                else
                {
                    this.Show();
                }
            }
        }