Validate user’s license

This function loads file registration.lic from your application location (for example: C:\Program Files\YourApp\registration.lic) and checks its validity. You can change location of file or use VerifyLicenseXML function of TreeksLicensingLibrary.LicenseVerification object.

//You can generate and get your public key via toolbox. Never add private key into your source code.
private const string MyPublicKey = "Put your PUBLIC key XML here.";

private TreeksLicensingLibrary.LicenseVerification verification = new TreeksLicensingLibrary.LicenseVerification(MyPublicKey);

// string ErrorMessage returns more detailed info on why was license recognized as invalid
// LicenseObject contains information about license, like owner, expiration date (if any), etc.
public bool IsLicenseValid(ref string ErrorMessage = "", ref TreeksLicensingLibrary.License LicenseObject = null)
{

    string LicenseFilePath = IO.Path.GetDirectoryName(Reflection.Assembly.GetExecutingAssembly().Location) + "\\registration.lic";

    if (IO.FileExists(LicenseFilePath))
    {
        if (verification.VerifyLicenseFile(LicenseFilePath, ErrorMessage, LicenseObject))
        {
            return true;
        }
        else
        {
            return false;
        }
    }
    else
    {
        return false;
    }

}

'You can generate and get your public key via toolbox. Never add private key into your source code.
Private Const MyPublicKey As String = "Put your PUBLIC key XML here."
Private verification As New TreeksLicensingLibrary.LicenseVerification(MyPublicKey)

' String ErrorMessage returns more detailed info on why was license recognized as invalid
' LicenseObject contains information about license, like owner, expiration date (if any), etc.
Public Function IsLicenseValid(Optional ByRef ErrorMessage As String = "", Optional ByRef LicenseObject As TreeksLicensingLibrary.License = Nothing) As Boolean

    Dim LicenseFilePath As String = IO.Path.GetDirectoryName(Reflection.Assembly.GetExecutingAssembly().Location) & "\registration.lic"

    If IO.FileExists(LicenseFilePath) Then
        If verification.VerifyLicenseFile(LicenseFilePath, ErrorMessage, LicenseObject) Then
            Return True
        Else
            Return False
        End If
    Else
        Return False
    End If

End Function

'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
'This is Office VBA (Visual Basic for Applications) example   '
'''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''
Public Function CheckLicenceIsValid() As Boolean

'Initialize new instances of TLL objects
Dim objVerification As New TreeksLicensingLibrary.LicenseVerification
'This object will be loaded with details from license file
Dim objLicenseObject As New TreeksLicensingLibrary.License

'Declare working variables
Dim blnValid As Boolean
Dim strLicenseFilePath As String

'This variable will contain error details when verification fails. In the other words, it'll tell you why the license file was recognized as invalid. Will be empty on verification success
Dim strErrorMessage As String

'Change this public key to yours, you can generate it in LibraryToolbox.exe
objVerification.SetPublicKey "YourPublicKey"

'Change this path to yours
strLicenseFilePath = "d:\test.lic"

blnValid = objVerification.VerifyLicenseFile(strLicenseFilePath, strErrorMessage, objLicenseObject)

If blnValid = True Then
'Show info about valid license
MsgBox "Licence is Valid." & vbCr & vbLf & vbCr & vbLf & "Product: " & objLicenseObject.ProductName & vbCr & vbLf & "License owner: " & objLicenseObject.OwnerName
Else
'Show info about invalid license
MsgBox "Licence is Not Valid." & vbCr & vbLf & vbCr & vbLf & "Reason: " & strErrorMessage & vbCr & vbLf & vbCr & vbLf & "Contact Support"
End If

End Function