I'm making a tool using visual studio 2019.When I tried to click registration button and there's no errors. But when I opened the database and refresh the database table there's no data in the data table. Any support for this issue much appreciated. Thank you. Thank you. Thank you. Thank you. Thank you.

private void submitBtn_Click(object sender, EventArgs e)
    {
        //connection string
        SqlConnection conn = new SqlConnection(@"Data Source = (LocalDB)\MSSQLLocalDB; AttachDbFilename = C:\ImageSteganography_2\ImageSteganography\Database1.mdf; Integrated Security = True");
        //Connection open here   
        conn.Open();
        SqlCommand cmd = new SqlCommand();

        if (repeatPassBox.Text != string.Empty || passBox.Text != string.Empty || contactBox.Text != string.Empty || emailBox.Text != string.Empty || userBox.Text != string.Empty)
        {
            //Email Address
            if (validate_email.IsMatch(emailBox.Text) != true)
            {
                MessageBox.Show("Invalid Email Address!", "Invalid", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                emailBox.Focus();
            }

            //Contacts
            else if (validate_contact.IsMatch(contactBox.Text) != true)
            {
                MessageBox.Show("Contact accept numbers only (10 digit).", "Invalid", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                contactBox.Focus();
            }

            //Password
            else if (validate_password.IsMatch(passBox.Text) != true)
            {
                MessageBox.Show("Password must be atleast 8 to 15 characters. It should contain at least one Upper case and numbers.", "Invalid", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
                passBox.Focus();
            }

            //Repeat Password
            else if (passBox.Text != repeatPassBox.Text)
            {
                MessageBox.Show("Please enter both password same ", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);

            } 
            else
            {
                cmd = new SqlCommand("select * from Login where username='"   userBox.Text   "'", conn);
                
                SqlDataReader dr = cmd.ExecuteReader();
                if (dr.Read())
                {
                    dr.Close();
                    MessageBox.Show("Username Already exist please try another ", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
                }
                else
                {
                    dr.Close();
                    cmd = new SqlCommand("insert into Registration values(@username,@email,@contact,@password,@repeatPassword)", conn);
                    cmd.Parameters.AddWithValue("username", userBox.Text);
                    cmd.Parameters.AddWithValue("email", emailBox.Text);
                    cmd.Parameters.AddWithValue("contact", contactBox.Text);
                    cmd.Parameters.AddWithValue("password", passBox.Text);
                    cmd.Parameters.AddWithValue("repeatPassword", repeatPassBox.Text);
                    

                    cmd = new SqlCommand("insert into Login values(@username,@password)", conn);
                    cmd.Parameters.AddWithValue("username", userBox.Text);
                    cmd.Parameters.AddWithValue("password", passBox.Text);
                    cmd.ExecuteNonQuery();
                    MessageBox.Show("Register successful. Please login now.", "Done", MessageBoxButtons.OK, MessageBoxIcon.Information);
                    this.Hide();
                    LOGIN f1 = new LOGIN();
                    f1.ShowDialog();
                }
                conn.Close();
            }
        }
        else
        {
            MessageBox.Show("All input fields cannot be blank.", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
        }
    }

CodePudding user response：

You are setting the command parameters incorrectly: Try something like this:

cmd.Parameters.Add("@username", SqlDbType.NVarChar, 50).Value = userBox.Text;

Also, use two Executenonquerys one for registration and other for other table.

CodePudding user response：

This will fix a LOT of small issues in the original, some not-so-small, and should run faster as a bonus:

private (string, Control) CheckRegistrationData()
{
    //Email Address
    if (emailBox.Text == "" || validate_email.IsMatch(emailBox.Text) != true)
    {
        return ("Invalid Email Address!", emailBox);
    }
    
    //Contacts
    if (contactBox.Text == "" || validate_contact.IsMatch(contactBox.Text) != true)
    {
        return ("Contact accept numbers only (10 digit).", contactBox);
    }

    // Password
    if (passBox.Text == "" || validate_password.IsMatch(passBox.Text) != true)
    {
        return ("Password must be atleast 8 to 15 characters. It should contain at least one Upper case and numbers.");
    }

    //Repeat Password
    if (repeatPassBox.Text == "" || passBox.Text != repeatPassBox.Text)
    {
        return ("Please enter both password same ", repeatPassBox);
    }
     
    return ("", null);
}

private void submitBtn_Click(object sender, EventArgs e)
{
     var validationResult = CheckRegistrationData();
     if (!string.IsNullOrEmpty(validationResult.Item1))
     {
         MessageBox.Show(validationResult.Item1, "Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
         if (validationResult.Item2 is Control)
         {
             valiadtionResult.Item2.Focus();
         }
         return;
     }
     
     // VALIDATION COMPLETE

     string SQL = @"
IF EXISTS(SELECT 1 FROM Login WHERE Username= @username )
BEGIN
    RAISERROR('Username Already exist',16,1);
END
ELSE
BEGIN
    INSERT INTO Registration (Username, Email, Contact, PasswordHash)
    VALUES (@username,@email,@contact,@passwordHash);
    INSERT INTO Login (UserName, PasswordHash) VALUES (@username,@passwordHash);
END
";

    using (var conn = new SqlConnection(@"Data Source = (LocalDB)\MSSQLLocalDB; AttachDbFilename = C:\ImageSteganography_2\ImageSteganography\Database1.mdf; Integrated Security = True"))
    using (var cmd = new SqlCommand(SQL, conn))
    {   //Much better to replace AddWithValue() with Add() and provide explicit type information about the database columns.     
        cmd.Parameters.AddWithValue("@username", userBox.Text);
        cmd.Parameters.AddWithValue("@email", emailBox.Text);
        cmd.Parameters.AddWithValue("@contact", contactBox.Text);
        cmd.Parameters.AddWithValue("@passwordHash", BCrypt.Net.BCrypt.HashPassword(passBox.Text)); //Based on BCrypt.Net Nuget package

        try 
        {                     
            conn.Open();
            cmd.ExecuteNonQuery();
        }
        catch(SqlException ex) when (ex.Errors[0].Class == 16)
        {
            MessageBox.Show("Username Already exist please try another ", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            return; 
        }
        catch(Exception ex)
        {
            MessageBox.Show($"Error trying to create registration: {ex.Message}", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            return;
        }
    }

    MessageBox.Show("Register successful. Please login now.", "Done", MessageBoxButtons.OK, MessageBoxIcon.Information);
    this.Hide();
    var f1 = new LOGIN();
    f1.ShowDialog();
}