在ASP中传递参数时有一个很有用的系统函数Server.UrlEncode,可以将一些非字母数字、中文等符号转换成标准URL编码(其实就是16进制ASC码),这样就解决了参数传递乱码的问题。
Server.URLEncode("内容")
然后我以为也提供了Server.UrlDecode,但使用后却发现程序报错,原来系统并没有提供这个我想象中的解码函数。怎幺办,自己动手吧。
UrlEncode的原理其实很简单,就是将特殊字符转换成16进制ASC码值,那么译码函数就只要将16进制ASC转回对应的字符就OK了。
这是推荐的解码方法:
function URLDecode(strIn)
URLDecode = ""
Dim sl: sl = 1
Dim tl: tl = 1
Dim key: key = "%"
Dim kl: kl = Len(key)
sl = InStr(sl, strIn, key, 1)
Do While sl>0
If (tl=1 And sl<>1) Or tl<sl Then
URLDecode = URLDecode & Mid(strIn, tl, sl-tl)
End If
Dim hh, hi, hl
Dim a
select Case UCase(Mid(strIn, sl+kl, 1))
Case "U": 'Unicode URLEncode
a = Mid(strIn, sl+kl+1, 4)
URLDecode = URLDecode & ChrW("&H" & a)
sl = sl + 6
Case "E": 'UTF-8 URLEncode
hh = Mid(strIn, sl+kl, 2)
a = Int("&H" & hh) 'ascii码
If Abs(a)<128 Then
sl = sl + 3
URLDecode = URLDecode & Chr(a)
Else
hi = Mid(strIn, sl+3+kl, 2)
hl = Mid(strIn, sl+6+kl, 2)
a = ("&H" & hh And &H0F) * 2 ^12 Or ("&H" & hi And &H3F) * 2 ^ 6 Or ("&H" & hl And &H3F)
If a<0 Then a = a + 65536
URLDecode = URLDecode & ChrW(a)
sl = sl + 9
End If
Case Else: 'Asc URLEncode
hh = Mid(strIn, sl+kl, 2) '高位
a = Int("&H" & hh) 'ascii码
If Abs(a)<128 Then
sl = sl + 3
Else
hi = Mid(strIn, sl+3+kl, 2) '低位
a = Int("&H" & hh & hi) '非ascii码
sl = sl + 6
End If
URLDecode = URLDecode & Chr(a)
End select
tl = sl
sl = InStr(sl, strIn, key, 1)
Loop
URLDecode = URLDecode & Mid(strIn, tl)
End function
下面是另外一种解码方法:
Function URLDecode(enStr) 'URL解码函数
dim deStr
dim c,i,v
deStr=""
for i=1 to len(enStr)
c=Mid(enStr,i,1)
if c="%" then
v=eval("&h"+Mid(enStr,i+1,2))
if v<128 then
deStr=deStr&chr(v)
i=i+2
else
if isvalidhex(mid(enstr,i,3)) then
if isvalidhex(mid(enstr,i+3,3)) then
v=eval("&h"+Mid(enStr,i+1,2)+Mid(enStr,i+4,2))
deStr=deStr&chr(v)
i=i+5
else
v=eval("&h"+Mid(enStr,i+1,2)+cstr(hex(asc(Mid(enStr,i+3,1)))))
deStr=deStr&chr(v)
i=i+3
end if
else
destr=destr&c
end if
end if
else
if c="+" then
deStr=deStr&" "
else
deStr=deStr&c
end if
end if
next
URLDecode=deStr
end function
function isvalidhex(str)
isvalidhex=true
str=ucase(str)
if len(str)<>3 then isvalidhex=false:exit function
if left(str,1)<>"%" then isvalidhex=false:exit function
c=mid(str,2,1)
if not (((c>="0") and (c<="9")) or ((c>="A") and (c<="Z"))) then isvalidhex=false:exit function
c=mid(str,3,1)
if not (((c>="0") and (c<="9")) or ((c>="A") and (c<="Z"))) then isvalidhex=false:exit function
end function
经测试gb312格式的asp使用没有问题。
下面是另外一种方法,如果上面的方法出错,那么就用下面这个试试:
Function URLDecode(ByVal urlcode) 'URL解码函数
Dim start,final,length,char,i,butf8,pass
Dim leftstr,rightstr,finalstr
Dim b0,b1,bx,blength,position,u,utf8
On Error Resume Next
b0 = Array(192,224,240,248,252,254)
urlcode = Replace(urlcode,"+"," ")
pass = 0
utf8 = -1
length = Len(urlcode) : start = InStr(urlcode,"%") : final = InStrRev(urlcode,"%")
If start = 0 Or length < 3 Then URLDecode = urlcode : Exit Function
leftstr = Left(urlcode,start - 1) : rightstr = Right(urlcode,length - 2 - final)
For i = start To final
char = Mid(urlcode,i,1)
If char = "%" Then
bx = URLDecode_Hex(Mid(urlcode,i + 1,2))
If bx > 31 And bx < 128 Then
i = i + 2
finalstr = finalstr & ChrW(bx)
ElseIf bx > 127 Then
i = i + 2
If utf8 < 0 Then
butf8 = 1 : blength = -1 : b1 = bx
For position = 4 To 0 Step -1
If b1 >= b0(position) And b1 < b0(position + 1) Then
blength = position
Exit For
End If
Next
If blength > -1 Then
For position = 0 To blength
b1 = URLDecode_Hex(Mid(urlcode,i + position * 3 + 2,2))
If b1 < 128 Or b1 > 191 Then butf8 = 0 : Exit For
Next
Else
butf8 = 0
End If
If butf8 = 1 And blength = 0 Then butf8 = -2
If butf8 > -1 And utf8 = -2 Then i = start - 1 : finalstr = "" : pass = 1
utf8 = butf8
End If
If pass = 0 Then
If utf8 = 1 Then
b1 = bx : u = 0 : blength = -1
For position = 4 To 0 Step -1
If b1 >= b0(position) And b1 < b0(position + 1) Then
blength = position
b1 = (b1 xOr b0(position)) * 64 ^ (position + 1)
Exit For
End If
Next
If blength > -1 Then
For position = 0 To blength
bx = URLDecode_Hex(Mid(urlcode,i + 2,2)) : i = i + 3
If bx < 128 Or bx > 191 Then u = 0 : Exit For
u = u + (bx And 63) * 64 ^ (blength - position)
Next
If u > 0 Then finalstr = finalstr & ChrW(b1 + u)
End If
Else
b1 = bx * &h100 : u = 0
bx = URLDecode_Hex(Mid(urlcode,i + 2,2))
If bx > 0 Then
u = b1 + bx
i = i + 3
Else
If Left(urlcode,1) = "%" Then
u = b1 + Asc(Mid(urlcode,i + 3,1))
i = i + 2
Else
u = b1 + Asc(Mid(urlcode,i + 1,1))
i = i + 1
End If
End If
finalstr = finalstr & Chr(u)
End If
Else
pass = 0
End If
End If
Else
finalstr = finalstr & char
End If
Next
URLDecode = leftstr & finalstr & rightstr
End Function
Function URLDecode_Hex(ByVal h)
On Error Resume Next
h = "&h" & Trim(h) : URLDecode_Hex = -1
If Len(h) <> 4 Then Exit Function
If isNumeric(h) Then URLDecode_Hex = cInt(h)
End Function
该文章在 2024/11/16 17:56:15 编辑过