Const sBASE_64_CHARACTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/"

Function Base64encode(ByVal asContents)

Dim lnPosition

Dim lsResult

Dim Char1

Dim Char2

Dim Char3

Dim Char4

Dim Byte1

Dim Byte2

Dim Byte3

Dim SaveBits1

Dim SaveBits2

Dim lsGroupBinary

Dim lsGroup64

If Len(asContents) Mod 3 > 0 Then asContents = asContents & String(3 - (Len(asContents) Mod 3), " ")

lsResult = ""

For lnPosition = 1 To Len(asContents) Step 3

lsGroup64 = ""

lsGroupBinary = Mid(asContents, lnPosition, 3)

Byte1 = Asc(Mid(lsGroupBinary, 1, 1)): SaveBits1 = Byte1 And 3

Byte2 = Asc(Mid(lsGroupBinary, 2, 1)): SaveBits2 = Byte2 And 15

Byte3 = Asc(Mid(lsGroupBinary, 3, 1))

Char1 = Mid(sBASE_64_CHARACTERS, ((Byte1 And 252) \ 4) + 1, 1)

Char2 = Mid(sBASE_64_CHARACTERS, (((Byte2 And 240) \ 16) Or (SaveBits1 * 16) And &HFF) + 1, 1)

Char3 = Mid(sBASE_64_CHARACTERS, (((Byte3 And 192) \ 64) Or (SaveBits2 * 4) And &HFF) + 1, 1)

Char4 = Mid(sBASE_64_CHARACTERS, (Byte3 And 63) + 1, 1)

lsGroup64 = Char1 & Char2 & Char3 & Char4

lsResult = lsResult + lsGroup64

Next

Base64encode = lsResult

End Function