by htmlcoder (1 Submission)
Category: Internet/HTML
Compatability: ASP (Active Server Pages)
Difficulty: Beginner
Date Added: Sat 1st January 2022
Rating: 
(1 Votes)
HTML Decode. The reverse of the htmlencode. Now with unicode and emoji support
VBcoders <%
Option Explicit
Dim objHelper
Set objHelper = New HtmlEntityToUnicode
Response.Write(objHelper.HtmlDecode("<br/><br/>hi 💚 green heart! purple heart 💜 ! "))
Set objHelper = Nothing
Class HtmlEntityToUnicode
dim BITS_TO_A_BYTE
dim BYTES_TO_A_WORD
dim BITS_TO_A_WORD
Dim m_lOnBits(30)
Dim m_l2Power(30)
Sub Class_Initialize()
BITS_TO_A_BYTE = 8
BYTES_TO_A_WORD = 4
BITS_TO_A_WORD = 32
m_lOnBits(0) = CLng(1)
m_lOnBits(1) = CLng(3)
m_lOnBits(2) = CLng(7)
m_lOnBits(3) = CLng(15)
m_lOnBits(4) = CLng(31)
m_lOnBits(5) = CLng(63)
m_lOnBits(6) = CLng(127)
m_lOnBits(7) = CLng(255)
m_lOnBits(8) = CLng(511)
m_lOnBits(9) = CLng(1023)
m_lOnBits(10) = CLng(2047)
m_lOnBits(11) = CLng(4095)
m_lOnBits(12) = CLng(8191)
m_lOnBits(13) = CLng(16383)
m_lOnBits(14) = CLng(32767)
m_lOnBits(15) = CLng(65535)
m_lOnBits(16) = CLng(131071)
m_lOnBits(17) = CLng(262143)
m_lOnBits(18) = CLng(524287)
m_lOnBits(19) = CLng(1048575)
m_lOnBits(20) = CLng(2097151)
m_lOnBits(21) = CLng(4194303)
m_lOnBits(22) = CLng(8388607)
m_lOnBits(23) = CLng(16777215)
m_lOnBits(24) = CLng(33554431)
m_lOnBits(25) = CLng(67108863)
m_lOnBits(26) = CLng(134217727)
m_lOnBits(27) = CLng(268435455)
m_lOnBits(28) = CLng(536870911)
m_lOnBits(29) = CLng(1073741823)
m_lOnBits(30) = CLng(2147483647)
m_l2Power(0) = CLng(1)
m_l2Power(1) = CLng(2)
m_l2Power(2) = CLng(4)
m_l2Power(3) = CLng(8)
m_l2Power(4) = CLng(16)
m_l2Power(5) = CLng(32)
m_l2Power(6) = CLng(64)
m_l2Power(7) = CLng(128)
m_l2Power(8) = CLng(256)
m_l2Power(9) = CLng(512)
m_l2Power(10) = CLng(1024)
m_l2Power(11) = CLng(2048)
m_l2Power(12) = CLng(4096)
m_l2Power(13) = CLng(8192)
m_l2Power(14) = CLng(16384)
m_l2Power(15) = CLng(32768)
m_l2Power(16) = CLng(65536)
m_l2Power(17) = CLng(131072)
m_l2Power(18) = CLng(262144)
m_l2Power(19) = CLng(524288)
m_l2Power(20) = CLng(1048576)
m_l2Power(21) = CLng(2097152)
m_l2Power(22) = CLng(4194304)
m_l2Power(23) = CLng(8388608)
m_l2Power(24) = CLng(16777216)
m_l2Power(25) = CLng(33554432)
m_l2Power(26) = CLng(67108864)
m_l2Power(27) = CLng(134217728)
m_l2Power(28) = CLng(268435456)
m_l2Power(29) = CLng(536870912)
m_l2Power(30) = CLng(1073741824)
End Sub
Public Function HTMLDecode(sText)
Dim regEx
Dim matches
Dim match
sText = Replace(sText, """, Chr(34))
sText = Replace(sText, "<" , Chr(60))
sText = Replace(sText, ">" , Chr(62))
sText = Replace(sText, "&" , Chr(38))
sText = Replace(sText, " ", Chr(32))
Set regEx= New RegExp
With regEx
.Pattern = "&#(\d+);" 'Match html unicode escapes
.Global = True
End With
Set matches = regEx.Execute(sText)
'Iterate over matches
For Each match in matches
'For each unicode match, replace the whole match, with the ChrW of the digits.
sText = Replace(sText, match.Value, "\U"&WordToHex(match.SubMatches(0)))
Next
HTMLDecode = sText
End Function
Private Function WordToHex(lValue)
Dim lByte
Dim lCount
For lCount = 0 To 3
lByte = RShift(lValue, lCount * BITS_TO_A_BYTE) And m_lOnBits(BITS_TO_A_BYTE - 1)
WordToHex = Right("0" & Hex(lByte), 2) & WordToHex
Next
End Function
Private Function RShift(lValue, iShiftBits)
If iShiftBits = 0 Then
RShift = lValue
Exit Function
ElseIf iShiftBits = 31 Then
If lValue And &H80000000 Then
RShift = 1
Else
RShift = 0
End If
Exit Function
ElseIf iShiftBits < 0 Or iShiftBits > 31 Then
Err.Raise 6
End If
RShift = (lValue And &H7FFFFFFE) \ m_l2Power(iShiftBits)
If (lValue And &H80000000) Then
RShift = (RShift Or (&H40000000 \ m_l2Power(iShiftBits - 1)))
End If
End Function
End Class
%>
