(VB.NET) Extract PKCS7 from MIME and Decrypt

Extracts the base64-encoded PKCS7 body of a MIME message to a file, and then decrypts using Chilkat Crypt2.

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' This example assumes the Chilkat API to have been previously unlocked.
' See Global Unlock Sample for sample code.

Dim mime As New Chilkat.Mime

Dim success As Boolean = mime.LoadMimeFile("c:/aaworkarea/EmailInBytes.txt")
If (success <> True) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


success = mime.SaveBody("c:/aaworkarea/smime.p7m")
If (success <> True) Then
    Debug.WriteLine(mime.LastErrorText)
    Exit Sub
End If


Dim crypt As New Chilkat.Crypt2

success = crypt.AddPfxSourceFile("c:/aaworkarea/my.pfx","pfxPassword")
If (success = False) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


' Indicate the public-key (PKCS7) encryption/decryption should be used:
crypt.CryptAlgorithm = "pki"

Dim inPath As String = "c:/aaworkarea/smime.p7m"
Dim outPath As String = "c:/aaworkarea/decrypted.dat"

success = crypt.CkDecryptFile(inPath,outPath)
If (success = False) Then
    Debug.WriteLine(crypt.LastErrorText)
    Exit Sub
End If


Debug.WriteLine("Success.")