Document Object

Encapsulates a multi-page document with support for raster and SVG images, bookmarks, annotations and text data.

Object Model

Syntax

JavaScript

function Leadtools.Documents.Document()

Remarks

The Document class provides uniform support for any type of document. The actual data behind can be a PDF document, Microsoft Word document, TIFF image, AutoCAD DWG drawing or any other of the hundreds of different raster, document or vector file formats supported by LEADTOOLS. Document encapsulates the common functionality needed to access this data in a uniform manner with the same properties, methods and data structures.

Document Viewer

Leadtools.Documents is used as an input to the LEADTOOLS DocumentViewer, which can be used to view the document and its pages with thumbnails, virtualization, text search and annotation support.

Creating a Document Class

A Document instance be obtained using the following:

Method	Description
DocumentFactory.LoadFromUri	Create a new instance from a document stored in a remote URL.
DocumentFactory.LoadFromCache	Loads a previously saved document from the cache.

Encryption

In most cases, the Document is ready to use after it has been obtained. However, some documents such as PDF can be encrypted and require a password before they can be parsed and used. Most of the properties and methods of Document will throw an error if the document has not been decrypted. IsEncrypted can be used to check if the document is encrypted and if so, Decrypt must be called with a password obtained from the user to unlock the document. When that happens, the value of IsDecrypted becomes true and the document is ready to be used. Note that IsEncrypted will stay true to indicate the original state of the document.

Document Identifier

Each document has a unique identifier that is set at creation time by the framework. This is stored in the DocumentId property. The ID is important when using the document with the cache system and is the only value needed to re-construct completely the document from the cache.

Caching

Documents can contain large number of pages and huge amount of data. Storing all this data in the physical memory is not feasible in most situations. Therefore, the Document class was designed to use an external caching system to store previously requested document sections and document modifications.

Structure and Table of Contents

DocumentStructure manages the structure of the document. This includes the bookmarks that represent the table of contents. They can be accessed through the Structure property of Document.

Pages

DocumentPages manages the pages of the document. It can be accessed through the Pages property of Document. DocumentPages is a standard JavaScript array; you can use any of the collection methods to add, remove, insert, get, set and iterate through the DocumentPage items. The DocumentPage is the main entry point for using the documents in a viewer or converter application. It contains functions to retrieve or update the raster or SVG image of the page, text data, annotations and hyperlinks.

Metadata

The metadata includes default values added by the service when the document is loaded or created, as well as any other data extracted from the document file itself such as author, subject and any keywords stored by other applications.

Properties

The following properties are part of Document and contain useful information:

DocumentId: The unique identifier of this document.
Name: The optional name of this document.
MimeType: The MIME type of the document.
Uri: The URL to the original document physical location.
IsDownloaded: Determines if the document was downloaded into the cache or a temp file.
IsReadOnly: Determines if the document is read-only and cannot be changed.
FileLength: The length of the original document file or URL in bytes.

Global Document Settings

The Document class contains the following to manage global settings used throughout the document.

Images: Manages the raster and SVG image settings of the document.
Annotations: Manages the annotations settings of the document.
Text: Manages the text and OCR recognition settings of the document.
Barcodes: Manages the barcode settings of the document.

Document Units

Document uses independent units of 1/720 of an inch for all items. This value is stored in UnitsPerInch constant (720). Refer to Documents Library Coordinate System for more information.

Example

JavaScript

function documentExample() {
   // Load a new document
   var url = "http://demo.leadtools.com/images/pdf/leadtools.pdf";
   lt.Documents.DocumentFactory.loadFromUri(url, null)
      .done(function (document) {
         console.log("General");
         console.log("  DocumentId:" + document.documentId);
         console.log("  Uri:" + document.uri);
         console.log("  IsDownloaded:" + document.isDownloaded);
         console.log("  IsReadOnly:" + document.isReadOnly);
         console.log("  MimeType:" + document.mimeType);
         console.log("  IsEncrypted:" + document.isEncrypted);
         console.log("  IsDecrypted:" + document.isDecrypted);
         console.log("Metadata");
         for (var i = 0; i < document.metadata.length; i++)
            console.log("  ", document.metadata[i]);
         console.log("Annotations");
         console.log("  AnnotationsUri:" + document.annotations.annotationsUri);

         console.log("Images");
         console.log("  IsSvgSupported:" + document.images.isSvgSupported);
         console.log("  isSvgViewingPreferred:" + document.images.isSvgViewingPreferred);
         console.log("  DefaultBitsPerPixel:" + document.images.defaultBitsPerPixel);
         console.log("  ThumbnailPixelSize:" + document.images.thumbnailPixelSize);

         console.log("Pages");
         console.log("  Count:" + document.pages.length);

         for (var i = 0; i < document.pages.length; i++) {
            var page = document.pages[i];
            console.log("    PageNumber:" + page.pageNumber);
            console.log("      OriginalPageNumber:" + page.originalPageNumber);
            console.log("      Size:" + page.size.width + "," + page.size.Height);
            console.log("      Resolution:" + page.resolution);
            console.log("      IsDeleted:" + page.isDeleted);

            console.log("     Annotations");
            console.log("       IsAnnotationsModified:" + page.isAnnotationsModified);
            console.log("       HasEmbeddedAnnotations:" + page.hasEmbeddedAnnotations);
         }

         console.log("--------");
      })
      .fail(function (jqXHR, statusText, errorThrown) {
         alert("Error loading document " + errorThrown);
      });
}