Getting a single file (with convenience jQuery event handler)

$('#open #chooseFile').change(function(e){
    var fileList = e.target.files;
    // get the one and only file
    var file = fileList[0];
    // further process file content...
    var reader = new FileReader();
    reader.readAsText(file, "text/plain");      
    reader.onload = localLoaded;
    reader.onerror = localError;
    // ...
});

Getting multiple files:

$('#open #chooseFile').change(function(e){
    var fileList = e.target.files;
    // loop over the files

    for (var i=0, file; file=fileList[i]; i++) {
        var reader = new FileReader();
        reader.readAsText(file, "text/plain");      
        reader.onload = localLoaded;
        reader.onerror = localError;
        // ...
    }
});