Private Function ComputeHash(ByVal _req As Request) As String
Dim _key As Strig={ Secret Key Provided by OG}
Dim datatocomputeHash As String = quot;{_req.amount}{_req.authKey}{_req.currency}{_req.merchantCode}{_req.pc}{_req.referenceID}{_req.sourceCurrency}{_req.timeStamp}{_req.tunnel}{_req.userReference}"
Return GetHashValue(datatoHash, _key)
Public Function GetHashValue(ByVal datatocomputeHash As String, ByVal HashKey As String) As String
Dim hmac As HMACSHA256 = New HMACSHA256(System.Text.Encoding.UTF8.GetBytes(HashKey))
Dim computedHash As String = convertToHex(hmac.ComputeHash(System.Text.UTF8Encoding.[Default].GetBytes(datatocomputeHash)))
Private Function convertToHex(ByVal data As Byte()) As String
Dim sb As System.Text.StringBuilder = New System.Text.StringBuilder(data.Length)
For Each b As Byte In data
sb.AppendFormat("{0:X2}", CInt(b))