Get Selection Size in Pixels

Question

I can't seem to figure this out.
var oCurSelection = activeDocument.selection;
var aSelSize = new Array;
aSelSize = oCurSelection.bounds;
I want to take a selection, make a new document at the selection size, and copy the selection to the new document. However, in the Data Browser, under activeDocument.selection.bounds, I see:
"Error: General Photoshop error occurred. \n. The command \"Get\" is not currently available."
What does this mean? A function I copied from these forums to detect a Selection (detectSelection) says there is a selection. Why can't my code see it?
Thanks,
Matthew Pfluger

Answer 1

Thanks, Xbytor, for all your help. Here is a copy of my completed script. Please note, all, that it has not been thoroughly tested.
// (c) Copyright 2008. Digital Age Media Services, LLC. All rights reserved.
// Written by Matthew Pfluger
// With the help of Xbytor on the Adobe User-to-User forums
// enable double-clicking from Mac Finder or Windows Explorer
#target photoshop
// this command only works in Photoshop CS2 and higher
// bring application forward for double-click events
app.bringToFront();
// ensure that there is at least one document open; if not, display error message
if (documents.length == 0) {
alert("There are no documents open.");
// ensure that a selection exists; if not, display error message
else if (!detectSelection()) {
alert("You must first create a selection.");
// if both a document and a selection exist and the selection isn't empty, then proceed
else {
// remember unit settings
var originalRulerUnits = preferences.rulerUnits;
// main
try {
// Get information about Current Selection
var docSource = activeDocument;
var oCurSelection = docSource.selection;
var aSelSize = GetSelectionBounds(docSource);
// Calculate width and height in given units
var width = aSelSize[2] - aSelSize[0];
var height = aSelSize[3] - aSelSize[1];
var lResolution = docSource.resolution;
// Create new filename so we don't overwrite any files
var sDocName = GetNewDocName(docSource);
var sFilePath = docSource.path.fsName + "\\" + sDocName + ".jpg";
var oMode = docSource.mode;
// Copy Selection
oCurSelection.copy()
// Add new document
var docNew = app.documents.add(width, height, lResolution, sDocName);
app.activeDocument = docNew;
docNew.mode = oMode;
// Copy image to new document
docNew.paste()
// Save New Document as JPEG
jpgFile = new File(sFilePath);
jpgSaveOptions = new JPEGSaveOptions();
jpgSaveOptions.embedColorProfile = true;
jpgSaveOptions.formatOptions = FormatOptions.STANDARDBASELINE;
jpgSaveOptions.matte = MatteType.NONE;
jpgSaveOptions.quality = 9;
docNew.saveAs(jpgFile, jpgSaveOptions, true, Extension.LOWERCASE);
// Close document without saving
docNew.close(SaveOptions.DONOTSAVECHANGES);
// display error message
catch (e) {
// throw e;
alert("An unknown error has occurred. Copy selection to new JPEG file failed.");
// restore original unit setting
preferences.rulerUnits = originalRulerUnits;
function GetNewDocName(docSource){
var sPath = docSource.path.fsName;
// count number of JPEGs in the activeDocument's parent folder
var lJPEGcount = CountFiles(sPath, "*.jpg")
// New FileName based on activeDocument.Name
// Also, ensure no repeat FileNames
return docSource.name.slice(0, -4) + " - Selection_" + lJPEGcount;
// Count the number of files in a given folder that match a given mask
function CountFiles(sFolderPath, sMask) {
// create folder object from input
var oFolder = new Folder (sFolderPath);
// create list of all JPEG files in selected folder
var docList = oFolder.getFiles(sMask);
return docList.length;
// check for a selection
function detectSelection() {
// declare local variables
var userHistory = activeDocument.activeHistoryState;
var isSelection = false;
// try Selection, Modify, Border and then undo if selection is detected
try {
activeDocument.selection.selectBorder(1);
activeDocument.activeHistoryState = userHistory;
isSelection = true;
// catch errors - no selection detected
catch (e) {}
return isSelection;
// tests for an empty selection
function selectionEmpty(){
var rc = true;
var doc = activeDocument;
try {
var me = doc.activeHistoryState;
doc.activeLayer.translate(0,1);
doc.activeHistoryState = me;
rc = false;
} catch (e) {
if (!e.toString().match(/initial bounding rectangle is empty/)) {
throw e;
return rc;
// returns the upper-left and lower-right points of the selection
function GetSelectionBounds (doc) {
var l = doc.artLayers.add();
doc.selection.fill(app.foregroundColor);
var bnds = l.bounds;
var hs = doc.historyStates;
if (hs[hs.length-2].name == "Layer Order") {
doc.activeHistoryState = hs[hs.length-4];
} else {
doc.activeHistoryState = hs[hs.length-3];
for (var i = 0; i < bnds.length; i++) {
bnds[i] = bnds[i].value;
return bnds;