示例#1
0
        private void sign_in_Click(object sender, EventArgs e)
        {
            String username, password;
            username = txtName.Text;
            password = txtpsd.Text;

            String myconn = "server = localhost;port=3306;user=root;password=123456;database=book";//数据库实例连接字符串
            MySqlConnection sq = new MySqlConnection(myconn);//建立连接
            sq.Open();//打开数据库
            string sql = string.Format("select count(*) from users where user_name='{0}'", username);
            MySqlCommand cmd = new MySqlCommand(sql, sq);
            int a = Convert.ToInt32(cmd.ExecuteScalar());//返回一个值,看用户是否存在
            string sql1 = string.Format("select count(*) from users where password='******'", password);
            MySqlCommand cmd1 = new MySqlCommand(sql1, sq);
            int b = Convert.ToInt32(cmd1.ExecuteScalar());
            if(a !=0 &&b!=0)
            {
                Form1 form = new Form1();
                form.Show();
            }
            else
            {
                DialogResult dr = MessageBox.Show("请检查您的用户名或密码是否正确,或注册新用户!","登录失败!",MessageBoxButtons.YesNo,MessageBoxIcon.Question);
                if(dr == DialogResult.Yes)//打开注册页面
                {
                    Lign_up form2 = new Lign_up();
                    form2.Show();
                }
                else
                {
                    this.Show();
                }

            }
        }
示例#2
0
 private void sign_up_Click(object sender, EventArgs e)
 {
     Lign_up form2 = new Lign_up();
     form2.Show();
 }