Does 'Back' reload the page?

oferu

Hi,

I notice that when I click the 'Back' button my previous script runs, i.e, all the php code runs (I previously thought that maybe the previous form displays without the code re-running).
However, I do not get the expected value displayed on my form.

After populating one element in formA with '17' (just any number) and submitting to formB (using POST ---> Redirect --> GET to avoid the 'expired from cache' message) I then click the 'Back' button and the 17 does not appear.
In the code below, after clickng 'Back', I see as output from the echo statement that rb_value[0] is, infact, '17' but within the form, the text element named rb_value[0] displays as empty.
Does anyone have suggestions why this might be?
It might have to do with that I do not understand what the 'back' button does. Or maybe with my PRG (post - redirect - get) model.
Thanks.

Here is part of the code:
echo "rb_value[0]=".$rb_value[0]; //After clicking 'Back' I see that rb_value[0] is 17

if (isset($rb_value[0])) {
$rb_val = $rb_value[0];
} else {
$rb_val = 1;
}

$line.= "<td width=\"20%\" valign=\"center\" align=\"left\"> ";

// This element displays as empty instead of the expected 17
$line.= "<input type=text name=\"rb_value[0]\" value=\"$rb_val\" size=\"25\" maxlength=25 </center> "
$line.= "</td> ";

Kudose

If you aren't caching, your browser requests new data every page load. Even if you click back (because there is no cache to go back to).

etully

I find that there's no consistent behavior. It usually comes from cache when I want the server to reload the page - and it forces a page refresh when I want it to come from cache.

oferu

Thanks for your reply.
I am not caching. In php.ini I have session.cache_limiter = nocache.
I just noticed when I looked at the html source by clicking 'View' / 'Page Source' in the browser:
<td width="20%" valign="center" align="left"> <input type=text name="rb_value[0]" value="17" size="25" maxlength=25 ></center> </td>
So why would the field on the form display as empty instead of 17?
It is true that when I last submitted from the script, the value on the form was empty, but now that I am clicking 'Back' the form should reload with the current value (which in the meantime was changed to 17).
Thanks.

etully

The act if clicking "view source" should theoretically display the HTML that is in your browser's memory so that the HTML you are seeing matches with the page that is being displayed. Instead, clicking view source often forces the browser to obtain a fresh copy of the page so what you see in the HTML is different than what you see in the browser window.

oferu

That's a good point. So I guess I cannot rely much on the 'View Source'.
I still do not see what my problem may be. Investigating further showed that the problem happens only in the second scenario below.

Scenario 1:
a. I enter formA
b. I leave a text element empty and submit
c. An error in red says that I must fill the field
d. I fill the field with a number (say 10)
e. submit
f. Reach formB
g. click 'Back'
h. I see 10 in the field, as expected

Scenario 2:
a. I enter formA
b. I remove the contents of a text element and submit (or fill and then delete (backspace))
c. An error in red says that I must fill the field
d. I fill the field with a number (say 10)
e. submit
f. Reach formB
g. click 'Back'
h. I see nothing in the field, although expected to see 10

Thanks.