Sample code for 30+ languages & platforms
VB.NET

RSA Sign Using Private Key from .pfx/.p12 to Base64 Signature

See more RSA Examples

Demonstrates how to RSA sign something using a private key loaded from a .pfx/.p12. The RSA signature is returned in Base64 encoded format.

Chilkat VB.NET Downloads

VB.NET
Dim success As Boolean = False

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

Dim rsa As New Chilkat.Rsa

' Load the .pfx/.p12
Dim pfx As New Chilkat.Pfx
success = pfx.LoadPfxFile("qa_data/pfx/myKey.p12","myPassword")
If (success = False) Then
    Debug.WriteLine(pfx.LastErrorText)
    Exit Sub
End If


' Get the default private key.

Dim privKey As New Chilkat.PrivateKey
success = pfx.PrivateKeyAt(0,privKey)
If (success = False) Then
    Debug.WriteLine(pfx.LastErrorText)
    Exit Sub
End If


' Import the private key into the RSA component:
success = rsa.UsePrivateKey(privKey)
If (success = False) Then
    Debug.WriteLine(rsa.LastErrorText)
    Exit Sub
End If


' Get the signature in base64
rsa.EncodingMode = "base64"

Dim strData As String = "This is the string to be signed."

' Sign the string using the sha256 hash algorithm.
' Other valid choices are "sha384", "sha512", "sha-1", "md2" and "md5".
Dim base64Sig As String = rsa.SignStringENC(strData,"sha256")

Debug.WriteLine(base64Sig)

Debug.WriteLine("Success!")