hi, i have a very simple html page with a global variable, a function
to increment its value, and a form that calls the function. however,
what happens is that every time i click the image, the page is
reloaded, and the value is reset to 1. is this what i should be
expecting? are global variables not persistent across reloads? if
this is the case, how can i set it up so that clicking the button
doesn't reload the page automatically, but rather just calls the
function. this is so frusterating :(
<html>
<head>
<script language="javas cript">
var a=1;
function incValue()
{
a = a+5;
}
</script>
</head>
<body>
<form>
<input type="image" src="one.gif" onclick="incVal ue()"/>
</form>
</body>
</html>
13  1722 
lost hope wrote:
(snip) ...are global variables not persistent across reloads?
Nope. http is stateless, reload or not.
if this is the case, how can i set it up so that clicking the button
doesn't reload the page automatically, but rather just calls the
function. this is so frusterating :(
(snip)
<input type="image"> is a graphical submit button. To avoid form
submission and the loading of a new document, try:
<a href="#" onclick="return incValue()"><im g src="one.gif" /></a>
var a = 1;
//watch that title bar !
document.title = 'a = ' + a;
function incValue()
{
a += 5;
document.title = 'a = ' + a;
return false; //kill link default
}
"RobB" <fe******@hotma il.com> wrote in message
news:11******** **************@ l41g2000cwc.goo glegroups.com.. . lost hope wrote:
(snip)
...are global variables not persistent across reloads?
Nope. http is stateless, reload or not.
if this is the case, how can i set it up so that clicking the button
doesn't reload the page automatically, but rather just calls the
function. this is so frusterating :(
(snip)
<input type="image"> is a graphical submit button. To avoid form
submission and the loading of a new document, try:
<a href="#" onclick="return incValue()"><im g src="one.gif" /></a>
var a = 1;
//watch that title bar !
document.title = 'a = ' + a;
function incValue()
{
a += 5;
document.title = 'a = ' + a;
return false; //kill link default
}
For me, just using <img src="image.gif" onclick="incVal ue()"> has worked.
The image isn't a link or form input, but it still responds to "onclick". I
don't know if it works in browsers other than IE, though.
Tony wrote: "RobB" <fe******@hotma il.com> wrote in message
news:11******** **************@ l41g2000cwc.goo glegroups.com.. . lost hope wrote:
(snip)
...are global variables not persistent across reloads?
Nope. http is stateless, reload or not.
if this is the case, how can i set it up so that clicking the
button doesn't reload the page automatically, but rather just calls the
function. this is so frusterating :(
(snip)
<input type="image"> is a graphical submit button. To avoid form
submission and the loading of a new document, try:
<a href="#" onclick="return incValue()"><im g src="one.gif" /></a>
var a = 1;
//watch that title bar !
document.title = 'a = ' + a;
function incValue()
{
a += 5;
document.title = 'a = ' + a;
return false; //kill link default
}
For me, just using <img src="image.gif" onclick="incVal ue()"> has
worked. The image isn't a link or form input, but it still responds to
"onclick". I don't know if it works in browsers other than IE, though.
That's ok, Image objects have onclick handlers too, in almost all
current browsers. Probably not a good habit to get into, however, as
they won't be spidered as links are. Add style="cursor:p ointer;" for a
more link-like appearance.
RobB wrote: Tony wrote: RobB wrote:
<snip> <a href="#" onclick="return incValue()"> ...
<snip> For me, just using <img src="image.gif" onclick="incVal ue()">
has worked. The image isn't a link or form input, but it
still responds to "onclick". I don't know if it works in
browsers other than IE, though.
That's ok, Image objects have onclick handlers too, in almost
all current browsers. Probably not a good habit to get into,
however, as they won't be spidered as links are. Add
style="cursor:p ointer;" for a more link-like appearance.
It is difficult to see what benefits can follow from having href="#"
spidered. What is lost when an onclick handler is used with an image is
any potential built into the browser for the use of an input device that
is not a 'pointing device' (such as a mouse). Denying the possibility of
using a keyboard for input (besides inconveniencing those that use
keyboards for input habitually) would mean that the result failed to be
accessible, and so would be illegal in some contexts throughout the
world (and antisocial in the rest). Although it would be possible to
implement the keyboard-based operation of the site within the script,
but that is a lot of additional work just to reproduce what browsers can
otherwise do for you (and even more complex to achieve reliably
cross-browser).
Richard.
lost hope wrote: hi, i have a very simple html page with a global variable, a function
to increment its value, and a form that calls the function. however,
what happens is that every time i click the image, the page is
reloaded, and the value is reset to 1. is this what i should be
expecting? are global variables not persistent across reloads? if
this is the case, how can i set it up so that clicking the button
doesn't reload the page automatically, but rather just calls the
function. this is so frusterating :(
<html>
<head>
<script language="javas cript">
var a=1;
function incValue()
{
a = a+5;
}
</script>
</head>
<body>
<form>
<input type="image" src="one.gif" onclick="incVal ue()"/>
</form>
</body>
</html>
If all you are using it for is to create a clickable image, just have
the input on its own with no form - then there's no form to submit
and no href to follow.
Users without JavaScript may wonder what the image is supposed to do
since they will see a pointer cursor when hovering over it, but
nothing will happen when they click.
--
Rob
Richard Cornford wrote: RobB wrote: Tony wrote: RobB wrote: <snip> <a href="#" onclick="return incValue()"> ... <snip> For me, just using <img src="image.gif" onclick="incVal ue()">
has worked. The image isn't a link or form input, but it
still responds to "onclick". I don't know if it works in
browsers other than IE, though.
That's ok, Image objects have onclick handlers too, in almost
all current browsers. Probably not a good habit to get into,
however, as they won't be spidered as links are. Add
style="cursor:p ointer;" for a more link-like appearance.
It is difficult to see what benefits can follow from having href="#"
spidered.
Hmm...didn't I say -
"Probably not a good habit to get into..."
....signifying that it was the *practice* of using image onclicks that
was being commented on, not the (trivial) example at hand. Certainly
agree about input devices; as well, all possibility of a default
alternative for JS-disabled users is removed - again, meaningless for
the above but worthy of thought as a general rule.
(snip)
Denying the possibility of using a keyboard for input...
would be illegal in some contexts throughout the world [ .. ]
Are there people doing time for Image.onclick? #:=0
hey guys,
thanks for all your help -- everything is much clearer now =) i
figured global state wasn't persistent across page reloads, but i
couldn't see why clicking the input (of type image) was causing the
refresh. now i understand. yay!
"RobB" <fe******@hotma il.com> wrote in message
news:11******** **************@ g14g2000cwa.goo glegroups.com.. . Tony wrote:
For me, just using <img src="image.gif" onclick="incVal ue()"> has
worked. The image isn't a link or form input, but it still responds to
"onclick". I don't know if it works in browsers other than IE, though.
That's ok, Image objects have onclick handlers too, in almost all
current browsers. Probably not a good habit to get into, however, as
they won't be spidered as links are. Add style="cursor:p ointer;" for a
more link-like appearance.
I didn't get the impression that this was something that needed to be
spidered, but that is a good point to remember.
"RobB" <fe******@hotma il.com> wrote in message
news:11******** **************@ g14g2000cwa.goo glegroups.com.. . Richard Cornford wrote:
"Probably not a good habit to get into..."
...signifying that it was the *practice* of using image onclicks that
was being commented on, not the (trivial) example at hand. Certainly
agree about input devices; as well, all possibility of a default
alternative for JS-disabled users is removed - again, meaningless for
the above but worthy of thought as a general rule.
Didn't think about that :0
(snip)
Denying the possibility of using a keyboard for input...
would be illegal in some contexts throughout the world [ .. ]
Are there people doing time for Image.onclick? #:=0
Damn! I better start changing my code before they come breaking in my front
door to haul me off! This thread has been closed and replies have been disabled. Please start a new discussion. Similar topics | |
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//Tony
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