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Visual Basic 6.0 Requires Chilkat v11.4.0+

Example: Mime.GetDecryptCertInfo method

Demonstrates the GetDecryptCertInfo method.

Chilkat Visual Basic 6.0 Downloads

Visual Basic 6.0
Dim success As Long
success = 0

Dim mime As New ChilkatMime

'  Load MIME that is has Content-Type like this:
'  Content-Type: application/pkcs7-mime; smime-type="enveloped-data"; name="smime.p7m"; smime-type="enveloped-data"
success = mime.LoadMimeFile("qa_data/mime/enveloped_data.eml")
If (success = 0) Then
    Debug.Print mime.LastErrorText
    Exit Sub
End If

'  Get information about the certificate that would be needed to decrypt.
'  An enveloped-data can potentially be decrypted by multiple certificates if it was encrypted in a way that allows it,
'  but in most cases, only a single certificate with associated private key (that of the message recipient) is possible.
Dim json As New ChilkatJsonObject
success = mime.GetDecryptCertInfo(json)
If (success = 0) Then
    Debug.Print mime.LastErrorText
    Exit Sub
End If

json.EmitCompact = 0
Debug.Print json.Emit()

'  Sample output:

'  {
'    "recipientInfo": [
'      {
'        "serial": "****",
'        "issuerCN": "****"
'      }
'    ]
'  }

'  Get each certificate's information like this:
Dim serial As String
Dim issuerCN As String

Dim i As Long
i = 0
Dim count As Long
count = json.SizeOfArray("recipientInfo")
Do While i < count
    json.I = i
    serial = json.StringOf("recipientInfo[i].serial")
    issuerCN = json.StringOf("recipientInfo[i].issuerCN")
    i = i + 1
Loop