expression.IsCertificateExpired
expression Required. An expression that returns one of the objects in the Applies To list.
Example
The following example prompts the user to select a digital signature with which to sign the active document in Microsoft Word. To use this example, open a document in Word and pass this function the name of a certificate issuer and the name of a certificate signer that match the Issued By and Issued To fields of a digital certificate in the Digital Certificates dialog box. This example will test to make sure that the digital signature that the user selects meets certain criteria, such as not having expired, before the new signature is committed to the disk.
Function AddSignature(ByVal strIssuer As String, _
strSigner As String) As Boolean
On Error GoTo Error_Handler
Dim sig As Signature
'Display the dialog box that lets the
'user select a digital signature.
'If the user selects a signature, then
'it is added to the Signatures
'collection. If the user doesn't, then
'an error is returned.
Set sig = ActiveDocument.Signatures.Add
'Test several properties before commiting the Signature object to disk.
If sig.Issuer = strIssuer And _
sig.Signer = strSigner And _
sig.IsCertificateExpired = False And _
sig.IsCertificateRevoked = False And _
sig.IsValid = True Then
MsgBox "Signed"
AddSignature = True
'Otherwise, remove the Signature object from the SignatureSet collection.
Else
sig.Delete
MsgBox "Not signed"
AddSignature = False
End If
'Commit all signatures in the SignatureSet collection to the disk.
ActiveDocument.Signatures.Commit
Exit Function
Error_Handler:
AddSignature = False
MsgBox "Action cancelled."
End Function