Hello,
I've written some Javascript code that uses XPCOM to allow a user to
download a file to there local disk. The problem is that this code only
works for ASCII files (maybe just 7-bit?), not binary. Binary files come
out corrupt. Does anyone know what I might be doing wrong?
---
var oURL = createInstance('@mozilla.org/network/standard-url;1',
'nsIURL');
oURL.spec = "http://www.example.com/somebinaryfile.doc";;
var ioServiceForDownload =
getService('@mozilla.org/network/io-service;1',
'nsIIOService');
var downloadChann =
ioServiceForDownload.newChannelFromURI(oURL).QueryInterface(
Components.interfaces.nsIHttpChannel);
var fp = downloadDocumentToDisk(title);
var fileOutputStream = createInstance("@mozilla.org/network/file-out
put-stream;1", "nsIFileOutputStream");
if(!fp) { return; }
fp.create(fp.NORMAL_FILE_TYPE, 0600);
fileOutputStream.init(fp, 2, 0600, false);
downloadChann.asyncOpen(saveFileListener, fileOutputStream);
var saveFileListener = {
onDataAvailable: function (channel, ctxt, inStr, sourceOffset,
count) {
var scriptableStream = toScriptableStream(inStr);
var theData = scriptableStream.read(count);
ctxt.write(theData, count);
return;
},
onStartRequest: function (channel, ctxt) {
consolePrint("onStartRequest, status: " + channel.status, true);
return;
},
onStopRequest: function (channel, ctxt, status) {
consolePrint("onStopRequest, status: " + status, true);
ctxt.close();
return;
}
};
function downloadDocumentToDisk(fileName)
{
var nsIFilePicker = Components.interfaces.nsIFilePicker;
var fp = Components.classes["@mozilla.org/filepicker;1"]
.createInstance(nsIFilePicker);
fp.init(top, "Save As", nsIFilePicker.modeSave);
fp.defaultString = fileName;
var rv = fp.show();
if(rv == nsIFilePicker.returnCancel) { return null; }
return fp.file;
}
function toScriptableStream(input) {
var SIStream = Components.Constructor(
'@mozilla.org/scriptableinputstream;1',
'nsIScriptableInputStream', 'init');
return new SIStream(input);
}
