ASP Request method not showing hidden line feed and tab characters

Question

I am trying to parse a POST request that includes "\n" and "\t" characters but as soon as I use a Request.Form to manipulate the data, those characters are no longer there. I used Wireshark to confirm that the characters are in the POST.

Can anyone please help?

Here is some code that reproduces the problem:

POST:

str = "accountRequest=<NewUser>" & vbLf & _
"Hello" & vbTab & "World" & vbLf & _
"</NewUser>"


Set objHTTP = Server.CreateObject("Msxml2.ServerXMLHTTP.3.0")
objHTTP.open "POST", "service.asp", False 
objHTTP.setRequestHeader "Content-Type", "application/x-www-form-urlencoded"
objHTTP.send str

response.Write(objHTTP.responseText)

Set objHTTP = Nothing

service.asp:

function w (str)
response.Write(str & "<br>")
end function

str = request.Form("accountRequest")

w(str)
w("Tabs: "& InStr(str,vbTab))
w("Lines: "& InStr(str,vbLf))

output:

HelloWorld
Tabs: 0
Lines: 0

By "no longer there" are you looking at them on an HTML page? They're not HTML, you won't see them. — Diodeus - James MacFarlane, Feb 28 '12 at 21:28
They're delimiters to data. I need to use them to split the POST content into an array and insert into a database. — greener, Feb 28 '12 at 21:33
Are these coming from a textarea? They should still be there then. — Diodeus - James MacFarlane, Feb 28 '12 at 21:35
No, they're coming from a remote server over which I don't have any control. This is an integration job. — greener, Feb 28 '12 at 21:36
Loop through the incoming string and dump the ASCII values of each character. (\n =10 and \t = 9) See if they're in there. — Diodeus - James MacFarlane, Feb 28 '12 at 21:39
I tried that but as soon as Request.From touches it, they're gone. — greener, Feb 28 '12 at 21:43

greener · Accepted Answer · 2012-03-02T03:23:04.927

1

Finally figured out that classic ASP Request.Form method doesn't preserve tabs if they're in the "\t" format (as opposed to URL encoded). However, PHP's $_POST does and so does the ASP.NET request method.

edited Mar 02 '12 at 03:23

answered Feb 29 '12 at 22:32

greener

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score 0 · Answer 2 · answered Feb 29 '12 at 13:26

If all you're trying to do is provide a delimiter to the data being passed via the querystring then I'd try to use a character that is more concrete than tabs and new lines.

| has historically been used a lot for situations like this I believe taht # is another value that makes it through the querystring without many problems.

I, personally, do not like relying on being able to pick Tab and NewLine out of a string value. Too prone to getting lost in certain situations when being passed here and there.

Just do this before sending it:

str = str.replace(VbTab,"#")
str = str.replace(VbLf,"|")

... and then the converse once on your target page and it should work fine.

I'm not the one sending it. The code I provided above is just a way to replicate the conditions I'm working under. I'm told from the folks who send the data that their method works fine with many other people. — greener, Feb 29 '12 at 16:13

ASP Request method not showing hidden line feed and tab characters

2 Answers2