Controlling Printing

[Terry Murray]

Hi Everybody:

I have been given the task of creating an online coupon. The major
challenge that I see right now is controlling printing so that only one
particular coupon can be printed. If anyone knows how I can disable the
printer after a coupon has been printed I would appreciate it. I understand
that I may have to write my code so that the user cannot get back to a
certain page where this coupon might be produced. But an undesirable
situation might arise when they are already at the coupon page and decide to
print another one which should not be allowed.

Any suggestions

Terry

[Aaron Bertrand [MVP]]

> particular coupon can be printed. If anyone knows how I can disable the

> printer after a coupon has been printed I would appreciate it.

You can't disable a user's printer. This is a good thing.

> situation might arise when they are already at the coupon page and decide

to

> print another one which should not be allowed.

Use client-side script to move to a print page, call window.print(), and
then redirect. Use server-side logic (session variable, database, what have
you) to enforce that the user can't go back to the same page.

[Sam \(primetlc® webmaster\)]

"Terry Murray" <tgmurray@rogers.com> wrote in message
news:IHwmb.800$7B1.729@news04.bloor.is.net.cable.r ogers.com...

> Hi Everybody:
>
> I have been given the task of creating an online coupon. The major
> challenge that I see right now is controlling printing so that only one
> particular coupon can be printed.

Can't be done mate......You can use cookies to prevent people from seeing
the same page twice, but people can get round that by disabling
cookies.....You can log their IP addresses, but most dialup users have
dynamic IP addresses......

Even if you implement both of these features, there's nothing to stop them
from hitting "Prnt Screen" and pasting the image into a grahics package like
Paint before printing them as many times as they want......

Having said that, one thought has just sprung to mind.....
You could get your coupon page to generate a code of semi-random numbers
based on an algorhythm that you define yourself......

Of course, this would mean you'd need some sort of hardware to validate them
at the point of sale.....Say a keypad so the numbers can be entered, a flter
to reject any codes that don't fit your algorhyhm, and a database showing
which codes have already been used......

[Sam \(primetlc® webmaster\)]

"Sam (primetlc® webmaster)" <prime-tee-ell-cee@tiscali.com> wrote in message
news:3f9ce5c1$1_2@mk-nntp-2.news.uk.tiscali.com...

>
> "Terry Murray" <tgmurray@rogers.com> wrote in message
> news:IHwmb.800$7B1.729@news04.bloor.is.net.cable.r ogers.com...

> > Hi Everybody:
> >
> > I have been given the task of creating an online coupon. The major
> > challenge that I see right now is controlling printing so that only one
> > particular coupon can be printed.

>
> Can't be done mate......You can use cookies to prevent people from seeing
> the same page twice, but people can get round that by disabling
> cookies.....You can log their IP addresses, but most dialup users have
> dynamic IP addresses......
>
> Even if you implement both of these features, there's nothing to stop them
> from hitting "Prnt Screen" and pasting the image into a grahics package

like

> Paint before printing them as many times as they want......
>
> Having said that, one thought has just sprung to mind.....
> You could get your coupon page to generate a code of semi-random numbers
> based on an algorhythm that you define yourself......
>
> Of course, this would mean you'd need some sort of hardware to validate

them

> at the point of sale.....Say a keypad so the numbers can be entered, a

flter

> to reject any codes that don't fit your algorhyhm, and a database showing
> which codes have already been used......

On second thoughts, this wouldnt work either.....There is nothing to stop
them from continually returning and generating a new coupon with a unique
code......

[Chris Hohmann]

"Sam (primetlc® webmaster)" <prime-tee-ell-cee@tiscali.com> wrote in
message news:3f9d0c29$1_2@mk-nntp-2.news.uk.tiscali.com...

>
> "Sam (primetlc® webmaster)" <prime-tee-ell-cee@tiscali.com> wrote in

message

> news:3f9ce5c1$1_2@mk-nntp-2.news.uk.tiscali.com...

> >
> > "Terry Murray" <tgmurray@rogers.com> wrote in message
> > news:IHwmb.800$7B1.729@news04.bloor.is.net.cable.r ogers.com...

> > > Hi Everybody:
> > >
> > > I have been given the task of creating an online coupon. The

major

> > > challenge that I see right now is controlling printing so that

only one

> > > particular coupon can be printed.

> >
> > Can't be done mate......You can use cookies to prevent people from

seeing

> > the same page twice, but people can get round that by disabling
> > cookies.....You can log their IP addresses, but most dialup users

have

> > dynamic IP addresses......
> >
> > Even if you implement both of these features, there's nothing to

stop them

> > from hitting "Prnt Screen" and pasting the image into a grahics

package

> like

> > Paint before printing them as many times as they want......
> >
> > Having said that, one thought has just sprung to mind.....
> > You could get your coupon page to generate a code of semi-random

numbers

> > based on an algorhythm that you define yourself......
> >
> > Of course, this would mean you'd need some sort of hardware to

validate

> them

> > at the point of sale.....Say a keypad so the numbers can be entered,

a

> flter

> > to reject any codes that don't fit your algorhyhm, and a database

showing

> > which codes have already been used......

>
> On second thoughts, this wouldnt work either.....There is nothing to

stop

> them from continually returning and generating a new coupon with a

unique

> code......

Actually, your idea has merit. The unique coupon code would need to
exist in the database to be valid for redemption. If not, the cashier
would be instructed to beat the customer about the head with their bar
code scanner.

HTH
-Chris Hohmann

[William Tasso]

Chris Hohmann wrote:

> ...
> The unique coupon code would need to
> exist in the database to be valid for redemption. If not, the cashier
> would be instructed to beat the customer about the head with their bar
> code scanner.
>

Why? don't cashiers carry wet fish any more?

--
William Tasso - [url]http://WilliamTasso.com[/url]