Javascript Access to File on local machine

Question

I want to open the files located on local drive using window.open().

When i try to access the file using window.open i am getting error "Access is denied."

Would somebody help to achieve this requirement in Internet explorer 8.0?

Thanks!

Answer 1

You can't. And thank God for that. Imagine how insecure the internet would've been if JS was able to access a client's file-system.
Of course, IE8 has the MS specific JScript superset (ActiveXObject), which does enable filesystem access:

var fileHandle,
    fs = new ActiveXObject("Scripting.FileSystemObject");
fileHandle = fs.OpenTextFile("C:\\path\\to\\file.tmp", 1, true);
fileHandle.Write('This is written to a file');
console.log(fileHandle.ReadLine());//will log what we've just written to the file

But this is non-standard, is - I think- no longer supported either, and doesn't work X-browser.
Here's the documentation. At the bottom there's a link to a more detailed overview of the properties and methods this object has to offer, as you can see, there's a lot to choose from

Answer 2

I'm adding this answer just to be complete, but so far as Web Pages go, Elias Van Ootegem's answer is correct: you can't (and shouldn't be able to) get to the local hard drive.

But .. you can isf your page is an HTA (HTML Application) :

HTML Application wiki

This is essentially a web page with .hta as the extension(usually) and some extra tags to tell IE that it's an HTA application, not a web page.

This is something that runs via the windows operating system and is so far as I'm aware only available for IE. The HTA application opens as a web page in IE, but without the usual web navigation / favourites toolbars etc.

Note that if you have a page on an internet server delivered as an HTA application, you're likely to cause virus scanners and firewalls to pop up because this would essenstially be running a script whcih could do manything to your computer. Not good for general internert stuff at all, but might be useful in a secure environment like an intranet where the source of the application is known to be safe.

To get to the file system, you can use javascript code like this :

// set up a Fils System Object variable.. 
var FSO = new ActiveXObject("Scripting.FileSystemObject");


// function to read a file
function ReadFile(sFile) {

var  f, ts;
var s="";
if(FSO.FileExists(sFile))
{
    f = FSO.GetFile(sFile); 
    ts = f.OpenAsTextStream(ForReading, TristateUseDefault); 
    if (!ts.AtEndOfStream) {s = ts.ReadAll( )}; 
    ts.Close( ); 
}
return s; 
}


alert(ReadFile("c:\\somefilename.txt");