# How To Submit A JavaScript Array Via XHR?

**URL:** <https://www.ruby-forum.com/t/how-to-submit-a-javascript-array-via-xhr/90621>\
**Category:** Rails\
**Created:** [March 30, 2007, 1:25pm UTC](https://www.ruby-forum.com/t/how-to-submit-a-javascript-array-via-xhr/90621 "2007-03-30T13:25:07Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![starmaerker](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/e9bcb4/32.png) [@starmaerker](https://www.ruby-forum.com/u/starmaerker)\
**Post date:** [March 30, 2007, 1:25pm UTC](https://www.ruby-forum.com/t/how-to-submit-a-javascript-array-via-xhr/90621/1 "2007-03-30T13:25:07Z")

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Hello,

I would like to create a button that, when clicked, pulls a subset of  
fields out a form on the same page and sends those fields’ values as  
an array to the server as an XHR.

The server’s response would then be used to update another element on  
the page.

So far I have got a button that pulls the subset of fields from the  
form and bundles their values into an array. But I don’t know how to  
submit this via XHR to the server.

My code looks like this:

\<%= button\_to\_function ‘Calculate price’, ‘bundle\_order();’ %\>

where bundle\_order() is a JavaScript function I wrote in application.js.

Can anyone help?

Thanks and regards,  
Andy S.

---

<div class="post-metadata">

**Author:** ![starmaerker](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/s/e9bcb4/32.png) [@starmaerker](https://www.ruby-forum.com/u/starmaerker)\
**Post date:** [March 30, 2007, 3:56pm UTC](https://www.ruby-forum.com/t/how-to-submit-a-javascript-array-via-xhr/90621/2 "2007-03-30T15:56:38Z")

</div>

On 30 Mar 2007, at 12:23, Andrew S. wrote:

> I would like to create a button that, when clicked, pulls a subset  
> of fields out a form on the same page and sends those fields’  
> values as an array to the server as an XHR.
> 
> The server’s response would then be used to update another element  
> on the page.
> 
> So far I have got a button that pulls the subset of fields from the  
> form and bundles their values into an array. But I don’t know how  
> to submit this via XHR to the server.

I just worked out how to do this. Here it is lest anyone else is  
interested:

1. Make a JavaScript function that returns a hash of the elements  
you wish to submit (not an array as I originally did). For example:

public/javascripts/application.js:

```
 function subset() {
   p1 = $F('dom-id-of-element-x')
   p2 = $F('dom-id-of-element-y')
   return $H({ x: p1, y: p2 });
 }

```

1. Use the link\_to\_remote helper and – here’s the part I was  
missing before – pass the :with key:

app/views/your\_controller/your\_action.rhtml:

```
 <%= link_to_remote 'Do something...',
                    :url => {:action => 'foo'},
                    :update => 'dom-id-to-update',
                    :with => 'subset()' %>

```

Hope that helps somebody.

Regards,  
Andy S.