Login form in VB.Net using Access database not working - sql

Question

I'm pretty sure this code used to allow me to login using the SQL statement below, but now it doesn't and just clears the text boxes.
There is also an error message that I would like displayed when the username and password do not match that in the database. This is, like the other one, a label that the visibility would need changing. I had this code:
Try
UserType = GetUserType(txtUsername.Text.Trim, txtPass.Text.Trim)
Catch ex As Exception
lblErrorMatch.Visible = True
End Try
However, this just clears the text boxes when the details do not match.
Imports System.Data.OleDb
Public Class frmLogin
Private DBCmd As New OleDbCommand
Private ConStr As String = "Provider=Microsoft.ACE.OLEDB.12.0;" &
"Data Source=|DataDirectory|\NewHotel.mdb;"
Private Sub btnLogIn_Click(sender As Object, e As EventArgs) Handles btnLogIn.Click
Dim UserType As Object
'Distinguishing beetween different users
If UserType Is Nothing Then
lblErrorEmpty.Visible = True
ElseIf UserType.ToString = "MANAGER" Then
frmHomeManager.Show()
ElseIf UserType.ToString = "RECEPTIONIST" Then
frmHomeReceptionist.Show()
End If
'Username and password not matching error message
'Empty textboxes error message
If txtUsername.Text = "" OrElse txtPass.Text = "" Then lblErrorEmpty.Visible = True : Exit Sub
txtUsername.Clear()
txtPass.Clear()
chkShowPass.Checked = False
End Sub
Private Function GetUserType(Username As String, Pass As String) As Object
Dim UserType As Object
'Pull username and password from the database to check against the entered login details
Using DBCon As New OleDb.OleDbConnection(ConStr),
DBCmd As New OleDbCommand("SELECT UserType FROM tblEmployeeLogin WHERE [Username] = #Username AND [Pass] = #Pass", DBCon)
DBCmd.Parameters.Add("#Username", OleDbType.VarChar).Value = Username
DBCmd.Parameters.Add("#Pass", OleDbType.VarChar).Value = Pass
DBCon.Open()
UserType = DBCmd.ExecuteScalar.ToString
End Using
Return UserType
End Function
Private Sub chkShowPass_CheckedChanged(sender As Object, e As EventArgs) Handles chkShowPass.CheckedChanged
'Show password when checkbox is checked
If chkShowPass.Checked = True Then
txtPass.PasswordChar = Nothing
ElseIf chkShowPass.Checked = False Then
txtPass.PasswordChar = "*"
End If
End Sub
Private Sub txtUsername_TextChanged(sender As Object, e As EventArgs) Handles txtUsername.TextChanged, txtPass.TextChanged
'Make error message disappear after text is enetered into either of the text boxes
lblErrorEmpty.Visible = False
lblErrorMatch.Visible = False
End Sub
Private Sub lnkClear_LinkClicked(sender As Object, e As LinkLabelLinkClickedEventArgs) Handles lnkClear.LinkClicked
txtUsername.Clear()
txtPass.Clear()
chkShowPass.Checked = False
End Sub
Private Sub btnClose_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles btnClose.Click
'Close the form down which stops the application
Me.Close()
End Sub
End Class
Thank you for your time :)

Answer 1

I recently made a login like what you're trying to do. Hopefully you understand this code and it helps:
Dim CMD As OleDbCommand = New OleDbCommand("SELECT * FROM Staff WHERE Login = '" & ID & "'", Con)
Dim user As String
Try
Con.Open()
Dim sdr As OleDbDataReader = CMD.ExecuteReader()
If (sdr.Read() = True) Then
user = sdr("Login")
MessageBox.Show("Login Successful!")
ActiveUser.IsLoggedIn = True
Else
MessageBox.Show("Invalid username or password!")
End If
Catch ex As Exception
MsgBox(ex.Message)
Finally
Con.Close()
End Try