How can I URL encode a string in Excel VBA?

Question

Is there a built-in way to URL encode a string in Excel VBA or do I need to hand roll this functionality?

Answer 1

Same as WorksheetFunction.EncodeUrl with UTF-8 support:

Public Function EncodeURL(url As String) As String
  Dim buffer As String, i As Long, c As Long, n As Long
  buffer = String$(Len(url) * 12, "%")

  For i = 1 To Len(url)
    c = AscW(Mid$(url, i, 1)) And 65535

    Select Case c
      Case 48 To 57, 65 To 90, 97 To 122, 45, 46, 95  ' Unescaped 0-9A-Za-z-._ '
        n = n + 1
        Mid$(buffer, n) = ChrW(c)
      Case Is <= 127            ' Escaped UTF-8 1 bytes U+0000 to U+007F '
        n = n + 3
        Mid$(buffer, n - 1) = Right$(Hex$(256 + c), 2)
      Case Is <= 2047           ' Escaped UTF-8 2 bytes U+0080 to U+07FF '
        n = n + 6
        Mid$(buffer, n - 4) = Hex$(192 + (c \ 64))
        Mid$(buffer, n - 1) = Hex$(128 + (c Mod 64))
      Case 55296 To 57343       ' Escaped UTF-8 4 bytes U+010000 to U+10FFFF '
        i = i + 1
        c = 65536 + (c Mod 1024) * 1024 + (AscW(Mid$(url, i, 1)) And 1023)
        n = n + 12
        Mid$(buffer, n - 10) = Hex$(240 + (c \ 262144))
        Mid$(buffer, n - 7) = Hex$(128 + ((c \ 4096) Mod 64))
        Mid$(buffer, n - 4) = Hex$(128 + ((c \ 64) Mod 64))
        Mid$(buffer, n - 1) = Hex$(128 + (c Mod 64))
      Case Else                 ' Escaped UTF-8 3 bytes U+0800 to U+FFFF '
        n = n + 9
        Mid$(buffer, n - 7) = Hex$(224 + (c \ 4096))
        Mid$(buffer, n - 4) = Hex$(128 + ((c \ 64) Mod 64))
        Mid$(buffer, n - 1) = Hex$(128 + (c Mod 64))
    End Select
  Next

  EncodeURL = Left$(buffer, n)
End Function