Currently, I'm using this code:
<?php
header('Content-type: application/force-download');
header('Content-Disposition: attachment; filename="'.$_POST['savename'].'.bob"');
echo($_POST['savedata'])
?>
It gets the data of a form, creates an attachment and sends it right back. This is useless, because the client has the data. I would like to rewrite it to:
myForm.onsubmit = SomeSaveToFileFunction()
Chrome can do that now.
<textarea></textarea><button>save</button>
document.getElementsByTagName('button')[0].onclick = function(){
var a = document.createElement('a');
a.href = 'data:text/plain;base64,'+
btoa(document.getElementsByTagName('textarea')[0].value);
a.textContent = 'download';
a.download = 'text.txt';
a.click();
}
The traffic might be useless, indeed. You're right. But like Pointy said, unfortunatelly there's no way by simply using javascript.
If you would just like to have your download implemented in a more elegant way (than page reload), make use of a "hidden" iframe, that loads the PHP-response. Maybe you could easily switch the PHP processing from POST to GET and ...
myForm.onsubmit = function(formValueSavename, formValueSavedata) {
// phpIframeRef addresses you hidden iframe
phpIframeRef.loaction.href = 'sendData.php?savename=' + formValueSavename + '&savedata=' + formValueSavedata;
}
You'll propably need some code to suppress your default handling of the form... which I don't know.
JavaScript cannot directly write files on a local computer, for obvious security reasons. However, you might be able to do just what you need using ActiveX object, but once again, it will only work with IE. You would then need equivalents like NPAPI to make it compatible with Chrome for example.
I guess you should stay with the way you actually do it, if it works like you want it to.
EDIT: I meant NPAPI and not "API". It lets you build plug-ins that work (kind of) the same way ActiveX do, and lets you do the same things.
