metadata - Is it possible to retrieve the last modified date of a file using Javascript?

Question

I have a set of links on a web page that link to PDF forms and .doc forms. These files are not stored in a database, simply stored as they are, locally on the server. Is it possible to retrieve the last modified date of a PDF or DOC file using Javascript? I don't have any specific need to use Javascript, but it is preferable.

UPDATE: Now that I realize that Javascript can't access the filesystem, is there an alternative method?

Answer 1

If it's on the same server as your calling function you can use XMLHttpRequest-

This example is not asynchronous, but you can make it so if you wish.

function fetchHeader(url, wch) {
    try {
        var req=new XMLHttpRequest();
        req.open("HEAD", url, false);
        req.send(null);
        if(req.status== 200){
            return req.getResponseHeader(wch);
        }
        else return false;
    } catch(er) {
        return er.message;
    }
}

alert(fetchHeader(location.href,'Last-Modified'));