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**Category:** Rails\
**Created:** [April 13, 2007, 3:09am UTC](https://www.ruby-forum.com/t/rjs-replacing-html-for-multiple-entries/91889 "2007-04-13T03:09:39Z")\
**Posts on this page:** 4\
**Page:** 1
**Author:**  [@el-gato](https://www.ruby-forum.com/u/el-gato)\
**Post date:** [April 13, 2007, 3:09am UTC](https://www.ruby-forum.com/t/rjs-replacing-html-for-multiple-entries/91889/1 "2007-04-13T03:09:39Z")
I have some elements that could show up on the same page multiple times.
Can anyone recommend a good way to do a replace\_html in this case? I
may have, for example, 3 posts that have been repeated on a page, all
with the same id (e.g,
) and I want to perform a
replace\_html against all of them. Doing it the normal way just replaces
the first. Can someone help? Thanks!
---
**Author:**  [@el-gato](https://www.ruby-forum.com/u/el-gato)\
**Post date:** [April 13, 2007, 4:58am UTC](https://www.ruby-forum.com/t/rjs-replacing-html-for-multiple-entries/91889/2 "2007-04-13T04:58:41Z")
Hi,
El Gato wrote:
> I may have, for example, 3 posts that have been repeated on
> a page, all with the same id (e.g,
>
> ) and I want
> to perform a replace\_html against all of them. Doing it the normal
> way just replaces the first. Can someone help? Thanks!
What you have is invalid HTML / XMTML. DOM ID’s must be unique within a
page for either Ajax or CSS to work properly (and don’t even get me
started
on browser behavior in quirks mode 😉 ). Run your page source against
[http://validator.w3.org/](http://validator.w3.org/). Assuming you really need to put the same post
on
the page multiple times, you’ll need to come up with a new naming
approach.
Something like sec1-post-11, sec2-post-11, etc. isn’t tough to either
render
or process on return.
hth,
Bill
---
**Author:**  [@el-gato](https://www.ruby-forum.com/u/el-gato)\
**Post date:** [April 13, 2007, 5:35am UTC](https://www.ruby-forum.com/t/rjs-replacing-html-for-multiple-entries/91889/3 "2007-04-13T05:35:38Z")
Bill W. wrote:
> What you have is invalid HTML / XMTML. DOM ID’s must be unique within a
> page for either Ajax or CSS to work properly (and don’t even get me
> started
> on browser behavior in quirks mode 😉 ). Run your page source against
> [http://validator.w3.org/](http://validator.w3.org/). Assuming you really need to put the same post
> on
> the page multiple times, you’ll need to come up with a new naming
> approach.
> Something like sec1-post-11, sec2-post-11, etc. isn’t tough to either
> render
> or process on return.
>
> hth,
> Bill
Actually, I knew that, and was originally using classes because of it,
but due to the documentation, thought I’d test id with ids to see if it
would work. So, is there no way to replace\_html against all elements of
a class? The problem with just using a unique naming scheme is that I
want _all_ of the elements of that class affected by the replace… I
can’t think of a clean way to interrogate the page about all of these
“unique” ids and change each one then.
---
**Author:**  [@el-gato](https://www.ruby-forum.com/u/el-gato)\
**Post date:** [April 13, 2007, 3:26pm UTC](https://www.ruby-forum.com/t/rjs-replacing-html-for-multiple-entries/91889/4 "2007-04-13T15:26:34Z")
Hi,
El Gato wrote:
> Actually, I knew that, and was originally using classes because of it,
> but due to the documentation, thought I’d test id with ids to see if it
> would work. So, is there no way to replace\_html against all elements of
> a class?
replace\_html replaces the content of a single DOM element, specified by
id.
To replace the contents of multiple DOM elements, you’d just iterate.
That’s very easy to do in your rjs template since it allows a mix of
straight ruby and rjs.
> The problem with just using a unique naming scheme is that I
> want _all_ of the elements of that class affected by the replace… I
> can’t think of a clean way to interrogate the page about all of these
> “unique” ids and change each one then.
Not sure what you mean by ‘interrogate the page’. It sounds like maybe
you’re coming from a background that’s mostly client-side js. In RoR,
every
thing that’s on the page, you put there from the server side where it’s
very
easy to keep track of. So I typically don’t think about interrogating
the
page, I think about interrogating the database or the session store to
find
out what’s on the page. In the example you’ve given so far, my
impression
is you’ve got one ‘thing’ that appears in different sections of the
page.
One (not tested, and it’s early here 😉 ) approach to replacing all
those
elements could look something like…
sections = [‘sec1-’, ‘sec2-’, 'sec3-]
sections.each do {|this\_section|
element\_to\_replace = this\_section+@post\_to\_replace
page.replace\_html(element\_to\_replace, …
}
I’m assuming the @post\_to\_replace was identified in the controller
method.
The sections could, of course, be identified there too.
hth,
Bill