How to change the CKEDITOR parameter?

Question

CKEditor

Hello!
The form has a text box in which the user enters the URL and a text area that is filled using the CKEDITOR editor.
Here is how the editor is initiated:

CKEDITOR.replace('ae-textarea-text', {
        filebrowserImageUploadUrl: '/Sites/UploadImgToSite?Site=' + $("#SiteName").val(),
        height: 850,
        width: 800       
    });

/Sites/UploadImgToSite?Site is the path on the controller that should save the image with the "Site" parameter, the
image is saved, but the "Site" parameter always comes empty. But if I pre-register the value in the box url text, then everything is ok.
It turns out that when the page is loaded, CKEDITOR is initiated by an empty #SiteName value and does not take it further. What can be done? In addition to splitting the operation into two steps, taking the url in the first and passing it to the second page, where CKEDITOR is initiated .... which I really would not like.

Answer 1

CKEDITOR has no way to change filebrowserImageUploadUrl dynamically.
The simplest solution:

$("#SiteName").change(function () {
  setcookie('upload_site', $(this).val());
}).change();

And on the server side, getting the upload_site value from cookies instead of getting it from GET['Site'] as it is now.
Just in case, the implementation of setcookie

function setcookie(name, value, expires, path, domain, secure) {
    expires instanceof Date ? expires = expires.toGMTString() : typeof(expires) == 'number' && (expires = (new Date(+(new Date) + expires * 1e3)).toGMTString());
    var r = [name + "=" + escape(value)], s, i;
    for(i in s = {expires: expires, path: path, domain: domain}){
        s[i] && r.push(i + "=" + s[i]);
    }
    return secure && r.push("secure"), document.cookie = r.join(";"), true;
}

Answer 2

Try like this:

var editor = CKEDITOR.replace('ae-textarea-text', {
        filebrowserImageUploadUrl: '/Sites/UploadImgToSite',
        height: 850,
        width: 800       
    });
$('#SiteName').change(function() {
  editor.config.filebrowserImageUploadUrl = '/Sites/UploadImgToSite?Site=' + $("#SiteName").val();
});