When I try debugging this, it comes up with an error on the line "If txtUsername.Text = ds.Tables("AddressBook").Rows(inc).Item(1) Then". It says NullReferenceException was unhandled. Object reference not set to an instance of an object.
Public Class MainLogin
Dim MaxRows As Integer
Dim inc As Integer = 0
Dim con As New OleDb.OleDbConnection
Dim dbProvider As String
Dim dbSource As String
Dim dbPassword As String
Dim sql As String
Dim ds As New DataSet
Dim da As OleDb.OleDbDataAdapter
Dim LoginCorrect As Boolean = False
Dim NoRecordsLeft As Boolean = False
Private Sub MainLogin_Load(sender As System.Object, e As System.EventArgs) Handles MyBase.Load
dbProvider = "provider=Microsoft.ACE.OLEDB.12.0"
dbSource = "Data Source = G:\Sixth Form\Computing\Year 13\COMP4 - Project\Program Draft\DatabaseTest.accdb;" 'check drive letter before debugging
dbPassword = "Jet OLEDB:Database Password=database;"
con.ConnectionString = dbProvider & dbSource & dbPassword
con.Open()
sql = "SELECT * FROM tblPassword"
da = New OleDb.OleDbDataAdapter(Sql, con)
da.Fill(ds, "AddressBook")
con.Close()
End Sub
Private Sub btnLogin_Click(sender As System.Object, e As System.EventArgs) Handles btnLogin.Click
Do
If txtUsername.Text = ds.Tables("AddressBook").Rows(inc).Item(1) Then
If txtPassword.Text = ds.Tables("AddressBook").Rows(inc).Item(2) Then
LoginCorrect = True
Else
LoginCorrect = False
End If
Else
LoginCorrect = False
End If
inc = inc + 1
If inc = ds.Tables("AddressBook").Rows.Count Then
NoRecordsLeft = True
End If
Loop Until LoginCorrect = True Or NoRecordsLeft = True
If LoginCorrect = True Then
MessageBox.Show("You have succesfully logged in correctly!!", "WOOOOOOOOOOOOO!")
End If
If NoRecordsLeft = True Then
MessageBox.Show("Wrong username or password, please try again!!")
End If
End Sub
Private Sub btnChangePassword_Click(sender As System.Object, e As System.EventArgs) Handles btnChangePassword.Click
ChangePasswordBarcodeLogin.Show()
Me.Hide()
End Sub
End Class
