passing value from opener to popup and processing it server side, not client side. Cant use a GET

Question

I have an aspx web page (opener) which opens a popup window

In the popup window I need to retrieve the value of a hidden field which exists in the opener page.

So this is all straight forward using Javascript.

However, here’s the problem, I need the value of the hidden field to be processed SERVER side before the pop up page loads

(Basically, the hidden field contains XML which need to be deserialized server side and the data used to construct the DOM of the popup page)

So how do I pass the data in the hidden field of the opener, to get processed serverside in popup?

The data is Waaay too long to be passed as a GET. i.e. in the querystring of the popup page

What are the other options here?

1. Retrieve it using Javascript in popup, then do a postback to reload the page (very ugly)
2. Somehow post the data when opening the popup? Is this possible and can I stil pass other info via the querystring
3. Any other ideas?

Answer 1

My usual solution to this sort of issue is to use XmlHTTPRequest to post the XML to the server, which simply stores the XML against some unique ID such as a GUID and have the ID returned from the server.

The URL you provide for your popup would then only need to carry this ID rather than the whole XML. Now when the server code on the other end of that URL needs the XML it can use the ID to look up the XML (probably deleting it from its temporary store at the same time) and can process the XML as if had been posted in the request.

Answer 2

Edit: Sorry, I realize this doesn't answer your question. I didn't read it clearly enough and didn't realize you needed to do it server side. I suppose if you wanted to take this path, though, you could then AJAX up your page to build it.

Parent page:

 foo = 'bar'; 
 child = open ("popup.html");
 // you can now access the new windows functions with child.varname and child.function()

Child page:

 alert(window.opener.foo);

Should alert Foo. Therefore you can:

 somevar = window.opener.document.getElementById('id').value;

to get the field's value.

Answer 3

Have a form like this

<form method="POST" action="action.php" onsubmit="open_popup(this);">
    <input name="really-big-field" type="hidden">
</form>

also, javascript like this

function open_popup(form)
{
    window.open('action.php', 'actionpopup','width=400,height=300');
    form.target = 'actionpopup';
}

1. window.open() will open a popup like you want.

2. Setting the form's target to the opened popup will make sure that the form will POST to that popup.

3. Since a POST is made, you can send larger data than you can send using GET.

4. You can process the data server side in action.php (or in ASP.Net/VB file).