how to prevent to go to the previous page?

[Eric]

Hi,

the user gets a form to fill. All the filled values are put into session
variables.
I want to prevent that he could click to the previous arrow of the browser
and then comes back to the form. Is that possible with asp.net?

Or, is it possible to clear the session when leaving the form page by
clicking the previous arrow?

Thanks
Eric

[Alexey Smirnov]

Re: how to prevent to go to the previous page?

On Nov 9, 11:26 am, "Eric" <e...@sdsclem.p owrote:

Hi,
>
the user gets a form to fill. All the filled values are put into session
variables.
I want to prevent that he could click to the previous arrow of the browser
and then comes back to the form. Is that possible with asp.net?
>
Or, is it possible to clear the session when leaving the form page by
clicking the previous arrow?
>
Thanks
Eric

Hi Eric

this could do the trick

<script language="JavaS cript">
if(history.leng th>0)
history.go(+1);
</script>

If user disabled javascript that wouldn't work and you would need to
look for another approach.

Hope this helps

[Eric]

Re: how to prevent to go to the previous page?

Thanks a lot.
If you don't mind, could you tell me more (or refer) about the another
approach?
This is a good solution, but if possible, i would prefer a more waterproof
way.
Thanks

"Alexey Smirnov" <alexey.smirnov @gmail.comschre ef in bericht
news:66aaee6b-3923-4d24-9927-4a2e589df487@35 g2000pry.google groups.com...
On Nov 9, 11:26 am, "Eric" <e...@sdsclem.p owrote:

Hi,
>
the user gets a form to fill. All the filled values are put into session
variables.
I want to prevent that he could click to the previous arrow of the browser
and then comes back to the form. Is that possible with asp.net?
>
Or, is it possible to clear the session when leaving the form page by
clicking the previous arrow?
>
Thanks
Eric

Hi Eric

this could do the trick

<script language="JavaS cript">
if(history.leng th>0)
history.go(+1);
</script>

If user disabled javascript that wouldn't work and you would need to
look for another approach.

Hope this helps

[Joern Schou-Rode]

Re: how to prevent to go to the previous page?

On Sun, 09 Nov 2008 13:30:46 +0100, Eric <erl@sdsclem.po wrote:

This is a good solution, but if possible, i would prefer a more
waterproof way.

Make sure that the input form does not get cached client-side:

Response.Cache. SetCacheability (HttpCacheabili ty.NoCache)

Reject/redirect the user from the input form if the session variable is
already set:

if (Request.Sessio n["foo"] != null) Response.Redire ct("bar.aspx")

--
Joern Schou-Rode

http://malamute.dk/

[Mark Rae [MVP]]

Re: how to prevent to go to the previous page?

"Eric" <erl@sdsclem.po wrote in message
news:%23bQm7bmQ JHA.1160@TK2MSF TNGP02.phx.gbl. ..

>>the user gets a form to fill. All the filled values are put into session
>>variables.
>>I want to prevent that he could click to the previous arrow of the
>>browser
>>and then comes back to the form. Is that possible with asp.net?
>>>
>>Or, is it possible to clear the session when leaving the form page by
>>clicking the previous arrow?

>>
><script language="JavaS cript">
>if(history.len gth>0)
>history.go(+1) ;
></script>
>>
>If user disabled javascript that wouldn't work and you would need to
>look for another approach.

>
If you don't mind, could you tell me more (or refer) about the another
approach?
This is a good solution, but if possible, i would prefer a more waterproof
way.

This is a very common question - there are hundreds of articles about it on
the web:

http://www.google.co.uk/search?sourceid=navclient&hl=en-GB&ie=UTF-8&rlz=1T4GPTB_en-GBGB298GB298&q=%22ASP%2eNET%22+back+button+disable

There really is no 100% guaranteed method for this which will work in all
cases on all browsers on all platforms. Principally, this is because the
navigation buttons are part of the browser, not the web application...


--
Mark Rae
ASP.NET MVP

http://www.markrae.net

[Alexey Smirnov]

Re: how to prevent to go to the previous page?

On Nov 9, 1:30 pm, "Eric" <e...@sdsclem.p owrote:

Thanks a lot.
If you don't mind, could you tell me more (or refer) about the another
approach?
This is a good solution, but if possible, i would prefer a more waterproof
way.
Thanks

Another appoach is what Joern told you. You used a session for storing
the values, so you can check if session already has the values or not.
If session has stored values you would redirect to the next page.
There is another limit - session will not work if user has cookies
disabled. So, theoretically speaking, this is not a 100% solution. In
the same time you use session to store values and if session will not
work your form will not work as well. And if cookies are required to
use your site (it seems) then this maybe the best way to prevent
people from going back