login form authentication

Hi Vandna

Here i have Created Two Forms Form1 Which is MDI main Form and Another is LoginForm

Code for Login Form Login Button is below

I have Created Setting "LoggedInUser" in Project>Properties>Settings to Store Currently LoggedIn Username so that we can get username while logging out .

though if you dont Understand I have Included Complete Project Files(With Database) I have Coded .Link is at Bottom of the post :)

 private void btnLogin_Click(object sender, EventArgs e)
        {
            //Get username and passwod in String From TextBoxes
            string Username = txtUserName.Text.Trim();
            string Password = txtPassword.Text.Trim();
 
            //Open Connection
            SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True");
            con.Open();
 
            //Fire Query
            SqlCommand comm = new SqlCommand("Select * from tblUserLogin where username=@username and Userpwd=@password", con);
            comm.Parameters.AddWithValue("@username",Username);
            comm.Parameters.AddWithValue("@password",Password);
 
            DataTable dt = new DataTable();
            SqlDataAdapter da = new SqlDataAdapter(comm);
            da.Fill(dt);
 
            // if any record Found Give access to User 
            if (dt.Rows.Count > 0)
            {
 
               //Update The Status of user in Database
                comm = new SqlCommand("update tbluserLogin set userstatus=1 where username=@username", con);
                comm.Parameters.Clear();
                comm.Parameters.AddWithValue("@username", Username);
                comm.ExecuteNonQuery();
                con.Close();
 
                //Write CurrentlyLogged UserName in Settings 
                Properties.Settings.Default.CurrentLogedUser = Username;
 
                //Open Main MDI Form 
                Form1 f1 = new Form1();
                f1.Show();
 
                // Make TextBoxes Blank 
                txtUserName.Text = "";
                txtPassword.Text = "";
                //Hide the Login Window Dont Close it if you Close it It will Close Whole application
                this.Hide();
            }
            else
            {
                //Show Message If User have given False username and password
                MessageBox.Show("Access Denied!!Enter Correct Password");
            }
        }

Now for Logout In MDI Form Write Code Like Below to Update the Status

 private void logoutToolStripMenuItem_Click(object sender, EventArgs e)
        {
            string LoggedInUser = Properties.Settings.Default.CurrentLogedUser.ToString();
 
            //Open Connection
            SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True");
            con.Open();
 
            //Update The Status of user in Database When Logout
            SqlCommand comm = new SqlCommand("update tbluserLogin set userstatus=0 where username=@username", con);
            comm.Parameters.Clear();
            comm.Parameters.AddWithValue("@username", LoggedInUser);
            comm.ExecuteNonQuery();
 
 
            con.Close();
           //Show LoginForm again 
            Application.OpenForms["LoginForm"].Show();
     
            //Close the MDI Form
            this.Close();
 
        }

Download Project Files

5 Replies

Know the answer? Post it — somebody with the same question will find it here.

Kirtan Patel17y ago
Accepted answer
Hi Vandna

Here i have Created Two Forms Form1 Which is MDI main Form and Another is LoginForm

Code for Login Form Login Button is below

I have Created Setting "LoggedInUser" in Project>Properties>Settings to Store Currently LoggedIn Username so that we can get username while logging out .

though if you dont Understand I have Included Complete Project Files(With Database) I have Coded .Link is at Bottom of the post :)

private void btnLogin_Click(object sender, EventArgs e)
        {
            //Get username and passwod in String From TextBoxes
            string Username = txtUserName.Text.Trim();
            string Password = txtPassword.Text.Trim();

            //Open Connection
            SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True");
            con.Open();

            //Fire Query
            SqlCommand comm = new SqlCommand("Select * from tblUserLogin where username=@username and Userpwd=@password", con);
            comm.Parameters.AddWithValue("@username",Username);
            comm.Parameters.AddWithValue("@password",Password);

            DataTable dt = new DataTable();
            SqlDataAdapter da = new SqlDataAdapter(comm);
            da.Fill(dt);

            // if any record Found Give access to User
            if (dt.Rows.Count > 0)
            {

               //Update The Status of user in Database
                comm = new SqlCommand("update tbluserLogin set userstatus=1 where username=@username", con);
                comm.Parameters.Clear();
                comm.Parameters.AddWithValue("@username", Username);
                comm.ExecuteNonQuery();
                con.Close();

                //Write CurrentlyLogged UserName in Settings
                Properties.Settings.Default.CurrentLogedUser = Username;

                //Open Main MDI Form
                Form1 f1 = new Form1();
                f1.Show();

                // Make TextBoxes Blank
                txtUserName.Text = "";
                txtPassword.Text = "";
                //Hide the Login Window Dont Close it if you Close it It will Close Whole application
                this.Hide();
            }
            else
            {
                //Show Message If User have given False username and password
                MessageBox.Show("Access Denied!!Enter Correct Password");
            }
        }

Now for Logout In MDI Form Write Code Like Below to Update the Status

private void logoutToolStripMenuItem_Click(object sender, EventArgs e)
        {
            string LoggedInUser = Properties.Settings.Default.CurrentLogedUser.ToString();

            //Open Connection
            SqlConnection con = new SqlConnection(@"Data Source=.\SQLEXPRESS;AttachDbFilename=|DataDirectory|\Database1.mdf;Integrated Security=True;User Instance=True");
            con.Open();

            //Update The Status of user in Database When Logout
            SqlCommand comm = new SqlCommand("update tbluserLogin set userstatus=0 where username=@username", con);
            comm.Parameters.Clear();
            comm.Parameters.AddWithValue("@username", LoggedInUser);
            comm.ExecuteNonQuery();

            con.Close();
           //Show LoginForm again
            Application.OpenForms["LoginForm"].Show();

            //Close the MDI Form
            this.Close();

        }

Download Project Files
Vandana Sardana17y ago
Hi kirtan, the table name is: tbluserlogin and the fields are as follows: userId userName userstatus userPwd userConPwd on the login form i have two labels: UserName and Password. two textboxes: txtusername and txtpassword and have two buttons: Login and Cancel i have made the MDI form so after login control goes to MDI form. and on the MDI form i have given the Logout and Exit option under the toolstripmenuitem File. so when the user will click login the userstatus will be set to 1. and when the user will click logout or exit from the MDI form the user status will be set to 0. i am new to this programming world so not getting how to do it. please help me out with this.
Kirtan Patel17y ago
Hi Vandana

Tell Me the Column Names of Your table Having this information i will provide you the code
Vandana Sardana17y ago
iwant the exact code to proceed with this.
Niradhip Chakraborty17y ago
As soon as user logged in you update the database user status column as 1 and before logged out update the column as 0.