Simple Login Form In Desktop Application Using WinForm

In a desktop application, we also need a login form just like in a web application. I have developed a simple login page in the desktop using Windows Forms.

Login Form Sample

Simple Login Form In Desktop Application Using WinForm

Database Table

CREATE TABLE [dbo].[UserLogin](
[UserID] [INT] IDENTITY(1,1) NOT NULL,
[Username] [VARCHAR](50) NOT NULL,
[Password] [NVARCHAR](250) NOT NULL,
[PasswordSalt] [VARCHAR](50) NULL,
[IsActive] [BIT] NOT NULL,
[AddedOn] [DATETIME] NOT NULL,
CONSTRAINT [PK_UserLogin] PRIMARY KEY CLUSTERED
(
[UserID] ASC
)WITH (PAD_INDEX = OFF, STATISTICS_NORECOMPUTE = OFF, IGNORE_DUP_KEY = OFF, ALLOW_ROW_LOCKS = ON, ALLOW_PAGE_LOCKS = ON) ON [PRIMARY]
) ON [PRIMARY]
GO
ALTER TABLE [dbo].[UserLogin] ADD CONSTRAINT [DF_UserLogin_IsActive] DEFAULT ((0)) FOR [IsActive]
GO
Stored Procedure:
-- =============================================
-- Author: <Bhuban Rana>
-- Create date: <2018-12-24>
-- Description: <This Sp checks valid user in userlogin table>
-- =============================================
ALTER PROCEDURE [dbo].[usp_CheckValidUser]
@Username varchar(100),
@Password nvarchar(250)
AS
BEGIN
-- SET NOCOUNT ON added to prevent extra result sets from
-- interfering with SELECT statements.
SET NOCOUNT ON;
DECLARE @Message varchar(100),
@Data nvarchar(250),
@Success bit
IF EXISTS(SELECT * FROM UserLogin WHERE Username=@Username AND [Password]=@Password)
BEGIN
SET @Success=1;
SET @Message='Valid User';
END
ELSE
BEGIN
SET @Success=0;
SET @Message='Incorrect Username or Password!';
END
SELECT @Success AS Success,@Message AS [Message]
END

In Service Class,

public ResponseModel Login(LoginModel model) {
ResponseModel response = new ResponseModel();
try {
using(IDbConnection connection = DbConnection.DbConnect()) {
DynamicParameters parameters = new DynamicParameters();
parameters.Add("@Username", model.Username);
parameters.Add("@Password", model.Password);
response = SqlMapper.Query < ResponseModel > (connection, "[dbo].[usp_CheckValidUser]", parameters, commandType: CommandType.StoredProcedure).FirstOrDefault();
}
} catch (Exception ex) {
response.Success = false;
response.Message = ex.Message.ToString();
}
return response;
}

In Controller,

public class LoginController {
private LoginService _loginService;
public LoginController() {
_loginService = new LoginService();
}
}

Events

private void btnLogin_Click(object sender, EventArgs e) {
progressBar.Minimum = 0;
progressBar.Maximum = 100;
progressBar.Value = 10;
progressBar.Step = 10;
lblRequiredUname.Visible = false;
lblRequiredPwd.Visible = false;
if (string.IsNullOrEmpty(txtUsername.Text) && string.IsNullOrEmpty(txtPassword.Text)) {
lblRequiredUname.Visible = true;
lblRequiredPwd.Visible = true;
} else if (string.IsNullOrEmpty(txtUsername.Text.Trim())) {
lblRequiredUname.Visible = true;
} else if (string.IsNullOrEmpty(txtPassword.Text.Trim())) {
lblRequiredPwd.Visible = true;
} else {
progressBar.Visible = true;
if (!bgWorker.IsBusy) {
btnLogin.Enabled = false;
progressBar.Style = ProgressBarStyle.Marquee;
bgWorker.RunWorkerAsync();
}
}
}
private void bgWorker_DoWork(object sender, DoWorkEventArgs e) {
ResponseModel response = new ResponseModel();
LoginModel model = new LoginModel();
model.Username = txtUsername.Text.Trim();
// model.Password = txtPassword.Text.Trim();
string passwordSalt = string.Empty;
RegistrationModel registrationModel = loginController.GetUserDetailsByUsername(model.Username);
if (registrationModel != null) {
passwordSalt = registrationModel.PasswordSalt;
model.Password = StaticMethods.EncryptString(passwordSalt, txtPassword.Text.Trim());
response = loginController.Login(model);
if (response.Success) {
this.Invoke(new MethodInvoker(delegate() {
this.Hide();
using(Dashboard dashboard = new Dashboard()) {
dashboard.ShowDialog();
}
}));
} else {
this.Invoke(new MethodInvoker(delegate() {
txtUsername.ReadOnly = false;
txtPassword.ReadOnly = false;
}));
btnLogin.Enabled = false;
MessageBox.Show(response.Message, "Fail!", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
} else {
MessageBox.Show("Please enter valid username..", "Invalid Username!", MessageBoxButtons.OK, MessageBoxIcon.Warning);
}
}
private void bgWorker_RunWorkerCompleted(object sender, RunWorkerCompletedEventArgs e) {
progressBar.Style = ProgressBarStyle.Blocks;
btnLogin.Enabled = true;
}

Conclusion

After login, if the login process is successful, then it redirects to the homepage. Else, it shows an "Invalid Login" error message.