Logon Validation

Hey guys,

I'm very new to VB.net and am having a problem with a logon screen.

Here's the code i am using:

Main Form:

VB Code:

Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.Load
        Dim frmLogon As New LogonDialog()
        Dim bLogonSuccessful As Boolean = False
        Dim sFailureMessage As String
 
        If frmLogon.ShowDialog() = DialogResult.OK Then
 
            If frmLogon.txtUser.Text = "username" Then
                If frmLogon.txtPassword.Text = "password" Then
                    bLogonSuccessful = True
                Else
                    sFailureMessage = "Invalid Password!"
                End If
            Else
                sFailureMessage = "Invalid User ID!"
            End If
        Else
            sFailureMessage = "Logon Attempt Cancelled"
        End If
 
        If Not bLogonSuccessful Then
            MessageBox.Show(sFailureMessage, "Logon Failed", MessageBoxButtons.OK, MessageBoxIcon.Error)
            Me.Close()
        End If
    End Sub

Logon Form:

VB Code:

Private Sub cmdOK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdOK.Click
        Dim sUserID As String
        Dim sPassword As String
 
        If sUserID.Trim() = "" Then
            MessageBox.Show("UserID cannot be blank" & "Please enter a proper UserID", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtPassword.Select()
        Else
            Me.DialogResult = DialogResult.OK
        End If
    End Sub

This is the error i am getting when i click OK on the logon form:

Code:

---

An unhandled exception of type 'System.NullReferenceException' occurred in login.exe

Additional information: Object reference not set to an instance of an object.

---

__________

Any help would be greatly appreciated

Thanks guys

Longshot

*edit: vB code added*

Quote:

---

Originally posted by longshot_zero
Logon Form:

VB Code:

Private Sub cmdOK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdOK.Click
        Dim sUserID As String
        Dim sPassword As String
 
        If sUserID.Trim() = "" Then
            MessageBox.Show("UserID cannot be blank" & "Please enter a proper UserID", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtPassword.Select()
        Else
            Me.DialogResult = DialogResult.OK
        End If
    End Sub

---

ahh got it... a case of brain fade on my behalf...

the above should have read:

VB Code:

Private Sub cmdOK_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles cmdOK.Click
        Dim sUserID As String
        Dim sPassword As String
 
        sUserID = txtUsername
        sPassword = txtPassword
 
        If sUserID.Trim() = "" Then
            MessageBox.Show("UserID cannot be blank" & "Please enter a proper UserID", "Error", MessageBoxButtons.OK, MessageBoxIcon.Error)
            txtPassword.Select()
        Else
            Me.DialogResult = DialogResult.OK
        End If
    End Sub

However, for it to work i have also had to remove the ".trim()" from the code. Anyone know why this is?

Thanks in advance

Set a break point and step through your code...
Find where it has the error.