Visual Guard Class Library Documentation

How to integrate Visual Guard in a WinForm application

To integrate Visual Guard in your application you must:

Integration Demo

This demo shows how to integrate Visual Guard in WinForm 2.0 application

How to integrate Visual Guard 

Referencing Visual Guard assemblies

In order to use Visual Guard, you must add references to Visual Guard assemblies:

Note: In the list of assemblies, Visual Studio can display different versions of the Visual Guard assemblies. You must select the assembly corresponding to the version of the framework used in your project.

Add Visual Guard assemblies

If the assemblies does not appear in this list you can use the Browse tab and select them in the directory <Visual Guard installation directory>/bin/2.0  for .net 2.0 applications or <Visual Guard installation directory>/bin/1.1  for .net 1.1 applications.

Description of Visual Guard assemblies:

Adding Visual Guard in your code

There are 2 main classes in Visual Guard:


You must load the security before all other code. In this case you will be sure to set the security of all the objects of your application. If you load your main form before authenticating a user, Visual Guard will not automatically set the security of this form. In this case, you must set the security of this form after loading the permissions of the user (see the method VGSecurityManager.SetSecurity).

Authenticating a user in VB.Net project where the application framework is enabled

It is recommended to use the event MyApplication_Startup in order to load the security. When the user is not authenticated or authorized, you should set the property e.Cancel to true in order to stop the application. The following sample demonstrates how to use the login form provided by Visual Guard to authenticate the user.

Imports Novalys.VisualGuard.Security.WinForm
Imports System.Reflection
Imports Microsoft.VisualBasic.ApplicationServices
Namespace My
   Partial Friend Class MyApplication

        Private Sub MyApplication_Startup(ByVal sender As Object, ByVal e As StartupEventArgs) Handles Me.Startup
            Dim form As VGLoginForm = New VGLoginForm()
            If form.ShowDialog() <> DialogResult.OK Then
                e.Cancel = True
                Return
            End If
        End Sub
    End Class

End Namespace

Authenticating a user in your own login form

The following example demonstrates how to authenticate a user. This code can be inserted in the click event of the OK button in a login form:

[C#]
VGAuthenticationState state = VGSecurityManager.Authenticate(user.Text, password.Text);
if (state.IsFailed())
{
    if (state.IsCanceled()) return;
    if (state.IsCredentialInvalid())
    {
        if (state.IsLastBadLogin())
        {
            MessageBox.Show("Invalid user or password. The next bad login will lock your account.");
        }
        else
        {
            MessageBox.Show("Invalid user or password");
        }
    }
    else if (state.IsUserNotAuthorized())
    {
        MessageBox.Show("user not authorized to log on the application");
    }
    else if (state.IsUserAccountExpired())
    {
        MessageBox.Show("your account is no more valid. Contact your administrator");
    }
    else if (state.IsUserAccountNotYetAvailable())
    {
        MessageBox.Show("your account is not yet available.");
    }
    else if (state.IsUserAccountLockedOut())
    {
        MessageBox.Show("your account is locked. Contact your administrator.");
    }
}
else
{
    if (state.IsPasswordSecure())
    {
        this.DialogResult = DialogResult.OK;
        return;
    }
    else if (state.IsLastGraceLogon())
    {
        MessageBox.Show("You must change your password");
        ChangePassword form = new ChangePassword();
        form.ShowDialog();
    }
    else
    {
        MessageBox.Show("Your password is not enough secure. Do not forget to change it.");
    }
}

[Visual Basic]
Dim state As VGAuthenticationState = VGSecurityManager.Authenticate(userTextBox.Text, passwordTextBox.Text)
If state.IsFailed() Then
    Me.DialogResult = DialogResult.None
    If state.IsCanceled() Then Return
    If state.IsCredentialInvalid() Then
        If state.IsLastBadLogin() Then
        MessageBox.Show("Invalid user or password. The next bad login will lock your account.")
        Else
            MessageBox.Show("Invalid user or password")
        End If
    ElseIf state.IsUserNotAuthorized() Then
        MessageBox.Show("user not authorized to log on to the application")
    ElseIf state.IsUserAccountExpired() Then
        MessageBox.Show("your account is no more valid. Contact your administrator")
    ElseIf state.IsUserAccountNotYetAvailable() Then
        MessageBox.Show("your account is not yet available.")
    ElseIf state.IsUserAccountLockedOut() Then
        MessageBox.Show("your account is locked. Contact your administrator.")
    End If
Else
    Me.DialogResult = DialogResult.OK
    If state.IsPasswordSecure() Then
        Return
    ElseIf state.IsLastGraceLogon() Then
        MessageBox.Show("You must change your password")
        Dim form As ChangePassword = New ChangePassword
        form.ShowDialog()
    Else
        MessageBox.Show("Your password is not enough secure. Do not forget to change it.")
    End If
End If

Using the default login form provided by Visual Guard

If you prefer, you can use the default login form provided by Visual Guard. In this case you can use the following code:

[C#]
Novalys.VisualGuard.Security.WinForm.VGLoginForm login = new Novalys.VisualGuard.Security.WinForm.VGLoginForm();
login.HeaderDescription = login.HeaderDescription + Environment.NewLine + "(the default user is \"jsmith\" and its password \"pwd\")";
login.UserName = "jsmith";
if (login.ShowDialog() == DialogResult.OK)
{
    login.Dispose();
    Application.Run(new MDIForm());
}

[Visual Basic]
Dim login As New Novalys.VisualGuard.Security.WinForm.VGLoginForm
login.HeaderDescription = login.HeaderDescription + Environment.NewLine + "(the default user is ""jsmith"" and its password ""pwd"")"
login.UserName = "jsmith"
If login.ShowDialog() = DialogResult.OK Then
    login.Dispose()
    Application.Run(New MDIForm)
End If

Loading the security for a user authenticated by an external system (based on Windows Logon or another Single Sign-on)

In some case, you do not want to use the Visual Guard authentication mechanism (you can use the Windows logon for example). In this case you must use the VGSecurityManager.LoadSecurity method. This method will check the authorization of a user and will load the permissions granted to this user.

This example demonstrates how to use the Windows logon to identify the user:

[Visual Basic]
Dim state As VGAuthorizationState
state = VGSecurityManager.LoadSecurity (System.Security.Principal.WindowsIdentity.GetCurrent())
If state.IsFailed() Then
    If state.IsUserNotFound() Then
        MessageBox.Show("Your are not declared in the security repository")
    ElseIf state.IsUserNotAuthorized Then
        MessageBox.Show("Your are not authorized to log on to this application")
    End If
Else
    Application.Run(New MDIForm)
End If

[C#]
VGAuthorizationState state = VGSecurityManager.LoadSecurity (System.Security.Principal.WindowsIdentity.GetCurrent());
if (state.IsFailed())
{
    if (state.IsUserNotFound())
    {
        MessageBox.Show("Your are not declared in the security repository");
    }
    elseif (state.IsUserNotAuthorized())
    {
        MessageBox.Show("Your are not authorized to log on to this application")
    }
}
else
{
    Application.Run(new MDIForm())
}


If you need to secure only form class in your application, you do not need to add more code. Visual Guard can detect automatically all form creations and sets the security automatically. But, if you want to secure other types of class, you must do the following: