使用来自MySql的两个不同的表登录，它们有各自不同的windows窗体

Question

我想从数据库中登录两个不同的表，每个表都有自己的windows表单。

我有两张来自MySql的桌子

• SECRETARY_REGISTRATION
• 注册

他们有自己的窗口

• SECRETARY_REGISTRATION有HomePageSecretary
• 注册有HomePagePhysician

我只有一个登录表单为两个，它有用户名文本框和密码文本框和按钮的登录仅。

请帮帮我。谢谢。:)

SqlConnection con = new SqlConnection(@"Data Source = ArlineCuachon\SQLEXPRESS; Initial Catalog = CDSS;
                                            Integrated Security = true;");
        string query = "SELECT * FROM REGISTRATION WHERE RUsername = '" + UsernameLogin.Text.Trim() + "' AND RPassword = '" + PasswordLogin.Text.Trim() + "'";
            SqlDataAdapter sda = new SqlDataAdapter(query, con);
            DataTable dtbl = new DataTable();
            sda.Fill(dtbl);
            if (dtbl.Rows.Count == 1)
            {
                this.Hide();
                HomePagePhysician home = new HomePagePhysician();
                home.ShowDialog();

            }

            else

            {

                MessageBox.Show("You have entered wrong username or password!");

            }
        string query = "SELECT * FROM SECRETARY_REGISTRATION WHERE SUsername = '" + UsernameLogin.Text.Trim() + "' AND SPassword = '" + PasswordLogin.Text.Trim() + "'";
        SqlDataAdapter sda1 = new SqlDataAdapter(query, con);
        DataTable dtbl1 = new DataTable();
        sda1.Fill(dtbl1);
        if (dtbl1.Rows.Count == 1)
        {
            this.Hide();
            HomePageSecretary home = new HomePageSecretary();
            home.ShowDialog();
        }

        else

        {

            MessageBox.Show("You have entered wrong username or password!");

        }

Answer 1

您不需要编写两次代码，您可以使用一个调用(如下面的查询)签入两个表。

SELECT * FROM
(
    SELECT Col1,Col2,Col3...ColN, 'Registartion' as TypeOfLogin FROM REGISTRATION
    UNION
    SELECT Col1,Col2,Col3...ColN, 'Secretary Registration' as TypeOfLogin FROM SECRETARY_REGISTRATION 
) T
WHERE T.SUsername  = 'UserName' AND T.SPassword ='Somepassword'

若要区分用户的类型，可以使用列TypeOfLogin，如果值为Registartion load HomePagePhysician form of HomePageSecretary窗体

代码中还有其他关键问题，比如构建动态查询，理想情况下，您需要使用参数来避免任何SQL注入攻击。

了解有关SQL注入这里的更多信息。

要了解如何使用命令参数，可以读取这