Home>Network programming tutorial>ASP tutorial

There is only UrlEncode in ASP, but no solution to the Urldecode problem?

Author：Eve Cole Update Time：2025-03-16 18:32:01

This article mainly introduces the solution to the problem of only UrlEncode in ASP and no Urldecode? , if you need it, please refer to it

There is a very useful system function Server.UrlEncode when passing parameters in ASP. It can convert some special symbols of non-alphanumeric numbers into standard URL encoding (actually hexadecimal ASC code), which solves the parameter passing problem. I thought Server.UrlDecode was also provided, but after using it, I found that the program reported an error. It turned out that the system did not provide this decoding function as I imagined. What to do, do it yourself.

The principle of UrlEncode is actually very simple. It is to convert special characters into hexadecimal ASC code value, so the decoding function just needs to convert hexadecimal ASC back to the corresponding character and it will be OK.

  1. FunctionURLDecode(enStr)'URL decoding function
  2. dimdeStr
  3. dimc,i,v
  4. deStr=
  5. fori=1tolen(enStr)
  6. c=Mid(enStr,i,1)
  7. ifc=%then
  8. v=eval(&h+Mid(enStr,i+1,2))
  9. ifv<128then
  10. deStr=deStr&chr(v)
  11. i=i+2
  12. else
  13. ifisvalidhex(mid(enstr,i,3))then
  14. ifisvalidhex(mid(enstr,i+3,3))then
  15. v=eval(&h+Mid(enStr,i+1,2)+Mid(enStr,i+4,2))
  16. deStr=deStr&chr(v)
  17. i=i+5
  18. else
  19. v=eval(&h+Mid(enStr,i+1,2)+cstr(hex(asc(Mid(enStr,i+3,1)))))))))))
  20. deStr=deStr&chr(v)
  21. i=i+3
  22. endif
  23. else
  24. destr=destr&c
  25. endif
  26. endif
  27. else
  28. ifc=+then
  29. deStr=deStr&
  30. else
  31. deStr=deStr&c
  32. endif
  33. endif
  34. next
  35. URLDecode=deStr
  36. endfunction
  38. functionisvalidhex(str)
  39. isvalidhex=true
  40. str=ucase(str)
  41. iflen(str)<>3thenisvalidhex=false:exitfunction
  42. ifleft(str,1)<>%thenisvalidhex=false:exitfunction
  43. c=mid(str,2,1)
  44. ifnot(((c>=0)and(c<=9))or((c>=A)and(c<=Z)))thenisvalidhex=false:exitfunction
  45. c=mid(str,3,1)
  46. ifnot(((c>=0)and(c<=9))or((c>=A)and(c<=Z)))thenisvalidhex=false:exitfunction
  47. endfunction

There is no problem with using asp in gb312 format after testing.

Related Articles