How to get a hash of a string of text or binary data from the CryptoAPI

Public Function getHash(data As String, hashType As Integer) As String
Dim ht As Long
Dim sTemp As String
Dim sProv As String
Dim hLen As Long
Dim h As String
Dim hl As Long
 
'get hash type
If hashType = 0 Then
 'MD5
 ht = CALG_MD5
 hLen = 16
ElseIf hashType = 1 Then
 'SHA
 hLen = 20
 ht = CALG_SHA
Else
 getHash = ""
 Exit Function
End If
'--- Prepare string buffers
sTemp = vbNullChar
sProv = MS_DEF_PROV & vbNullChar
'---Gain Access To CryptoAPI
If Not CBool(CryptAcquireContext(cryptContext, sTemp, sProv, PROV_RSA_FULL, 0)) Then
 If Not CBool(CryptAcquireContext(cryptContext, sTemp, sProv, PROV_RSA_FULL, CRYPT_NEWKEYSET)) Then
 getHash = ""
 Exit Function
 End If
End If
'Create Empty hash object
If Not CBool(CryptCreateHash(cryptContext, ht, 0, 0, hl)) Then
 getHash = ""
 Exit Function
End If
'Hash the input string.
If Not CBool(CryptHashData(hl, data, Len(data), 0)) Then
 getHash = ""
 Exit Function
End If
h = String(20, vbNull)
'Get hash val
If Not CBool(CryptGetHashParam(hl, HP_HASHVAL, h, hLen, 0)) Then
 getHash = ""
 Exit Function
End If
getHash = h
 
End Function