//console.show();
saveAttachedPdfDocument('attachment.pdf');

function saveAttachedPdfDocument(attachmentName)
{
    var isDocumentModified = this.dirty;
    var dataObj = findDataObject(attachmentName);    

    if (dataObj == null)
        dataObj = createDataObjectFromFileAttachment(attachmentName);

    if (dataObj != null) { 
        this.exportDataObject({ cName: dataObj.name, bAllowAuth: true, nLaunch: 0 });
        // remove temporary data object
        this.removeDataObject(dataObj.name);
        // restore document state
        this.dirty = isDocumentModified;
    }
    else
        console.println('The attachment was not found or could not be exported.');
}

function findDataObject(dataObjectName)
{
    var dataObjectsCollection = this.dataObjects;
    
    if (dataObjectsCollection != null) {
        for (var i = 0; i < dataObjectsCollection.length; i++) {
            if (dataObjectsCollection[i].name == dataObjectName) {
                return dataObjectsCollection[i];
            }
        }
    }

    return null;
}

function createDataObjectFromFileAttachment(attachmentName)
{
    this.syncAnnotScan();
    var annots = this.getAnnots();
    for (var i = annots.length - 1; i >= 0; i--)
            if (annots[i].type == 'FileAttachment' && annots[i].attachment.name == attachmentName) 
                break;
    if (i != -1) {
        var attachmentObj = annots[i].attachment;
        // create temporary data object
        this.createDataObject(attachmentName, '');
        this.setDataObjectContents(attachmentName, attachmentObj.contentStream);
        var dataObj = this.getDataObject(attachmentName);
        return dataObj; 
    }
    else {
        console.println('Attachment not found.');
        return null;
    }
}