登錄為僅顯示一個值

Question

我希望我的表單顯示為我登錄的人。我有登錄表單，當您輸入密碼和用戶名時，它會打開電話簿表單，我希望在其中除其他所有內容外，還顯示我輸入的用戶名的標簽，現在只顯示角色，我在注冊表單中輸入

 public partial class PhoneBook : Form
    {
        Thread th;
        private string Role;
        SqlConnection con = Helper.GetConnectionStringDatabase();
        public PhoneBook(string role)
        {
            InitializeComponent();
            Role = role;
        }

        private void Biodata_Load(object sender, EventArgs e)
        {
            this.ActiveControl = tbName;
            tbName.Focus();
            Display();
            LoggedAs.Text = "You are logged in as: " + Role;
            if (Role != "Admin\t")
            {
                btnDelete.Enabled = false;
            }

        }

這是登錄代碼

public void btnLogin_Click(object sender, EventArgs e)
        {
            DataTable dt = new DataTable();

            //CheckForDatabaseExistance();

            using (SqlConnection con = Helper.GetConnectionStringDatabase())
            {

                SqlDataAdapter sda =
                    new SqlDataAdapter(
                        "SELECT Role FROM LOGIN WHERE UserName='" + tbUser.Text + "' AND Password='" + tbPassword.Text +
                        "' ", con);

                sda.Fill(dt);
            }
            CheckIfTxtBoxexAreNotEmpty();

            if (dt.Rows.Count == 1)
                {
                    this.Hide();
                    PhoneBook ss = new PhoneBook(dt.Rows[0][0].ToString());
                    ss.Show();
                }
            else
            {
                MessageBox.Show("Please check your username and password");
                tbUser.Clear();
                tbPassword.Clear();
            }
        }

Answer 1

首先在此行中選擇您的用戶名：

SqlDataAdapter sda = new SqlDataAdapter
(
    // Pick the right username-column
    "SELECT Role, Username FROM LOGIN WHERE UserName='" + tbUser.Text + "' AND Password='" + tbPassword.Text +
"' ", con);

然后像這樣修改構造器：

private string Role;
private string User;
public PhoneBook(string role, string user)
{
    InitializeComponent();
    Role = role;
    User = user;
}

然后只需更正您的電話：

PhoneBook ss = new PhoneBook(dt.Rows[0][0].ToString(), dt.Rows[1][0].ToString());

要么

PhoneBook ss = new PhoneBook(dt.Rows[0][0].ToString(), dt.Rows[0][1].ToString());

不知道索引

到此為止。 您在PhoneBook User將具有其用戶名。 然后，您可以簡單地將Role替換為User ：

private void Biodata_Load(object sender, EventArgs e)
{
    this.ActiveControl = tbName;
    tbName.Focus();
    Display(); //                               |
    //                                          v Here
    LoggedAs.Text = "You are logged in as: " + User + " - " + Role;
    if (Role != "Admin\t")
    {
        btnDelete.Enabled = false;
    }
}