(VB.NET) Extract a File from a .p7m (PKCS7 Signed-Data)

VB.NET example to extract the original file from a .p7m (Signed-Data PKCS7 Format) The .p7m contains the signed contents of the original file. It can be verified and restored by calling VerifyP7M.

Download: Chilkat .NET Assemblies

Dim crypt As New Chilkat.Crypt2()

'  Any string argument automatically begins the 30-day trial.
Dim success As Boolean
success = crypt.UnlockComponent("30-day trial")
If (success <> true) Then
    TextBox1.Text = TextBox1.Text & crypt.LastErrorText & vbCrLf
    Exit Sub
End If


Dim outFile As String
outFile = "/Users/chilkat/testData/pdf/sample.pdf"
Dim inFile As String
inFile = "/Users/chilkat/testData/p7m/sample.pdf.p7m"

'  Verify and restore the original file:
success = crypt.VerifyP7M(inFile,outFile)
If (success = false) Then
    TextBox1.Text = TextBox1.Text & crypt.LastErrorText & vbCrLf
    Exit Sub
End If


MsgBox("Success!")