Question

I’m building a bookmarklet for a service. I need to transfer data (url, text) from open window but I don’t know which would be the best method. GET limits the amount of data and ajax isn’t possible due cross-domain problem.

What would be the optimal way?

Answer 1

You could use POST if it’s a lot of data. Create a hidden iframe with a form with a textbox. Set the form method to post and the action to your service. Put the data into the textbox, attach the iframe to the document, and submit the form.

Try something like this:

  function postData (data, url, cb) {

    var f     = document.createElement('iframe'),
        fname = (+((''+Math.random()).substring(2))).toString(36);

    f.setAttribute('name', fname);
    f.setAttribute('id', fname);
    f.setAttribute('style', 'width:0;height:0;border:none;margin:none;padding:none;position:absolute;');

    document.body.appendChild(f);

    var frame = window.frames[fname], 
        doc   = frame.document,
        form  = doc.createElement('form'),
        text  = doc.createElement('textarea');

    text.setAttribute('name', 'data');
    text.appendChild(doc.createTextNode(data));

    form.setAttribute('action', url);
    form.setAttribute('method', 'post');
    form.appendChild(text);

    doc.body.appendChild(form);

    if (cb) { document.getElementById(fname).onload=cb; }

    doc.forms[0].submit();
  }

You can remove the iframe from the document in the callback if you want.