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documentId Property

Summary

ID of this attachment document.

Syntax

TypeScript

JavaScript

Object.defineProperty(DocumentAttachment.prototype, 'documentId', 
   get: function(), 
   set: function(value) 
)

documentId: string;

Property Value

ID of this attachment document. The default value is null.

Remarks

isEmbedded is set to true when embedded attachments are read from a document and the value of documentId will be null.

Application programs adding external attachments should set the value of isEmbedded to false and set documentId to the ID of the document representing the attachment.

For more information, refer to Document Attachments.

Example

Main.ts

DocumentHelper.ts

Main.js

DocumentHelper.js

Main.html

import { DocumentHelper } from "../../utilities/DocumentHelper"; 
import { DocumentFactory_CheckCacheInfoExample } from "../Factory/CheckCacheInfo"; 
 
export class DocumentAttachment_MainExample { 
   private el: HTMLElement; 
 
   public constructor() { 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
      DocumentHelper.initFactory(); 
   } 
 
   private urlToPdfFile = "http://localhost/images/pdf/portfolio/port1.pdf"; 
 
   public run(buttonID: string) { 
      document.getElementById(buttonID).onclick = this.onRun; 
   } 
 
   onRun = () => { 
      /* 
      The PDF document can be one of the following: 
      1. Normal PDF without attachments. Has one or more pages and no attachments. 
      2. Normal PDF with attachments. Has one or more pages and one or more attachments. 
      3. PDF Portfolio. Has a placeholder page and one or more attachments. 
 
      The value of LoadDocumentOptions.loadAttachmentsMode affects loading the documents as follows: 
 
      1. Normal PDF without attachments: Will not be affected. 
      2. Normal PDF with attachments: Number of pages is not affected. 
         Number of attachments is: 
            LoadAttachmentsMode = none then 0 
            LoadAttachmentsMode = asAttachments then number of attachments found in the document. 
      3. PDF Portfolio: Number of pages is: 
            LoadAttachmentsMode = none then 1 (the placeholder page) 
            LoadAttachmentsMode = asAttachments then 0 (the document has no pages). 
         Number of attachments is: 
            LoadAttachmentsMode = none then 0 
            LoadAttachmentsMode = asAttachments then number of attachments found in the document. 
      */ 
     const pdfUrl = this.urlToPdfFile; // URL to a PDF file as an input to this example 
      // First, load the document without attachments 
      console.log("Loading with DocumentLoadAttachmentsMode.none"); 
      const loadDocumentOptions = new lt.Document.LoadDocumentOptions(); 
      loadDocumentOptions.loadAttachmentsMode = lt.Document.DocumentLoadAttachmentsMode.none; 
      this.loadDocument(pdfUrl, loadDocumentOptions, (doc) => { 
         console.log("Document has " + doc.pages.count + " pages"); 
 
         // Find out if the document is portfolio 
         const isPortfolioValue = doc.metadata[lt.Document.LEADDocument.metadataKey_IsPortfolio]; 
         const isPortfolio = isPortfolioValue && isPortfolioValue.toLowerCase() === "true"; 
         console.log("isPortfolio:" + isPortfolio); 
 
         // Check that everything is as expected 
 
         // We should have 0 attachments since we did not instruct the toolkit to load these 
         if (doc.attachments.count != 0) throw new Error("Something went wrong"); 
 
         // We should have one or more pages regardless of whether the document is PDF portfolio 
         if (doc.pages.count === 0) throw new Error("Something went wrong"); 
 
         // Next, load the document with attachments 
         console.log("Loading with DocumentLoadAttachmentsMode.asAttachments"); 
         loadDocumentOptions.loadAttachmentsMode = lt.Document.DocumentLoadAttachmentsMode.asAttachments; 
         this.loadDocument(pdfUrl, loadDocumentOptions, (doc) => { 
            console.log("Document has " + doc.pages.count + " pages"); 
 
            // Find out if the document is portfolio 
            const isPortfolioValue = doc.metadata[lt.Document.LEADDocument.metadataKey_IsPortfolio]; 
            const isPortfolio = isPortfolioValue && isPortfolioValue.toLowerCase() === "true"; 
            console.log("isPortfolio:" + isPortfolio); 
 
            // Check that everything is as expected 
 
            // We may have 0 or more attachments depending on the file 
            console.log("Document has " + doc.attachments.count + " attachments"); 
 
            // We should have one or more pages unless this is PDF portfolio, then it will have 0 pages 
            if (isPortfolio) { 
               if (doc.pages.count !== 0) throw new Error("Something went wrong"); 
            } 
 
            // Extract all the embedded attachments into the cache 
            this.extractAttachments(doc, 0, () => { 
               console.log("Example done"); 
            }); 
         }); 
      }); 
   } 
 
   loadDocument = (url: string, loadDocumentOptions: lt.Document.LoadDocumentOptions, done: (doc: lt.Document.LEADDocument) => void) => { 
      DocumentHelper.log("Loading document " + url); 
      lt.Document.DocumentFactory.loadFromUri(url, loadDocumentOptions) 
      .done((doc) => { 
         DocumentHelper.log("Document loaded and has cache id: " + doc.documentId); 
         done(doc); 
      }) 
      .fail(DocumentHelper.showServiceError); 
   } 
 
   extractAttachments = (doc: lt.Document.LEADDocument, attachmentIndex: number, done: () => void) => { 
      if (attachmentIndex >= doc.attachments.count) { 
         done(); 
         return; 
      } 
 
      // Show info on this attachment 
      const attachment = doc.attachments.item(attachmentIndex); 
      console.log("Attachment number " + attachment.AttachmentNumber + "file name is '" + attachment.fileName +"' and length is " + attachment.fileLength + " bytes"); 
 
      // Save it into the cache 
      // Another option is to load it directly using lt.Document.DocumentFactory.loadDocumentAttachment to load it as a LEAD document 
      const saveAttachmentToCacheOptions = new lt.Document.SaveAttachmentToCacheOptions(); 
      saveAttachmentToCacheOptions.attachmentNumber = attachmentIndex + 1; 
      lt.Document.DocumentFactory.saveAttachmentToCache(doc, null, saveAttachmentToCacheOptions) 
         .done((attachmentDocumentId) => { 
            console.log("attachment " + saveAttachmentToCacheOptions.attachmentNumber + " saved into the cache with document ID = " + attachmentDocumentId); 
 
            // The attachment data can be downloaded using lt.Document.DocumentFactory.downloadDocumentData or loaded using DocumentFactory.loadFromCache 
 
            this.extractAttachments(doc, attachmentIndex + 1, done); 
         }) 
         .fail(DocumentHelper.showServiceError); 
   } 
}

export class DocumentHelper { 
   static showServiceError = (jqXHR, statusText, errorThrown) => { 
      alert("Error returned from service. See the console for details."); 
      const serviceError = lt.Document.ServiceError.parseError(jqXHR, statusText, errorThrown); 
      console.error(serviceError); 
   } 
 
   static log = (message: string, data?: any) => { 
      const outputElement = document.getElementById("output"); 
      if (outputElement) { 
         const time = (new Date()).toLocaleTimeString(); 
         const textElement = document.createElement("p"); 
         textElement.innerHTML = (outputElement.childElementCount + 1) + " [" + time + "]: " + message; 
         outputElement.insertBefore(textElement, outputElement.firstChild); 
      } 
 
      if (!data) 
         console.log(message); 
      else 
         console.log(message, data); 
   } 
 
   static initFactory = () => { 
      // To communicate with the DocumentsService, it must be running! 
      // Change these parameters to match the path to the service. 
      lt.Document.DocumentFactory.serviceHost = "http://localhost:40000"; 
      lt.Document.DocumentFactory.servicePath = ""; 
      lt.Document.DocumentFactory.serviceApiPath = "api"; 
   } 
}

import { DocumentHelper } from "../../utilities/DocumentHelper"; 
import { DocumentFactory_CheckCacheInfoExample } from "../Factory/CheckCacheInfo"; 
 
export class DocumentAttachment_MainExample { 
   constructor() { 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
      DocumentHelper.initFactory(); 
   } 
 
   urlToPdfFile = "http://localhost/images/pdf/portfolio/port1.pdf"; 
 
   run = (buttonID) => { 
      document.getElementById(buttonID).onclick = this.onRun; 
   } 
 
   onRun = () => { 
      /* 
      The PDF document can be one of the following: 
      1. Normal PDF without attachments. Has one or more pages and no attachments. 
      2. Normal PDF with attachments. Has one or more pages and one or more attachments. 
      3. PDF Portfolio. Has a placeholder page and one or more attachments. 
 
      The value of LoadDocumentOptions.loadAttachmentsMode affects loading the documents as follows: 
 
      1. Normal PDF without attachments: Will not be affected. 
      2. Normal PDF with attachments: Number of pages is not affected. 
         Number of attachments is: 
            LoadAttachmentsMode = none then 0 
            LoadAttachmentsMode = asAttachments then number of attachments found in the document. 
      3. PDF Portfolio: Number of pages is: 
            LoadAttachmentsMode = none then 1 (the placeholder page) 
            LoadAttachmentsMode = asAttachments then 0 (the document has no pages). 
         Number of attachments is: 
            LoadAttachmentsMode = none then 0 
            LoadAttachmentsMode = asAttachments then number of attachments found in the document. 
      */ 
     const pdfUrl = this.urlToPdfFile; // URL to a PDF file as an input to this example 
      // First, load the document without attachments 
      console.log("Loading with DocumentLoadAttachmentsMode.none"); 
      const loadDocumentOptions = new lt.Document.LoadDocumentOptions(); 
      loadDocumentOptions.loadAttachmentsMode = lt.Document.DocumentLoadAttachmentsMode.none; 
      this.loadDocument(pdfUrl, loadDocumentOptions, (doc) => { 
         console.log("Document has " + doc.pages.count + " pages"); 
 
         // Find out if the document is portfolio 
         const isPortfolioValue = doc.metadata[lt.Document.LEADDocument.metadataKey_IsPortfolio]; 
         const isPortfolio = isPortfolioValue && isPortfolioValue.toLowerCase() === "true"; 
         console.log("isPortfolio:" + isPortfolio); 
 
         // Check that everything is as expected 
 
         // We should have 0 attachments since we did not instruct the toolkit to load these 
         if (doc.attachments.count != 0) throw new Error("Something went wrong"); 
 
         // We should have one or more pages regardless of whether the document is PDF portfolio 
         if (doc.pages.count === 0) throw new Error("Something went wrong"); 
 
         // Next, load the document with attachments 
         console.log("Loading with DocumentLoadAttachmentsMode.asAttachments"); 
         loadDocumentOptions.loadAttachmentsMode = lt.Document.DocumentLoadAttachmentsMode.asAttachments; 
         this.loadDocument(pdfUrl, loadDocumentOptions, (doc) => { 
            console.log("Document has " + doc.pages.count + " pages"); 
 
            // Find out if the document is portfolio 
            const isPortfolioValue = doc.metadata[lt.Document.LEADDocument.metadataKey_IsPortfolio]; 
            const isPortfolio = isPortfolioValue && isPortfolioValue.toLowerCase() === "true"; 
            console.log("isPortfolio:" + isPortfolio); 
 
            // Check that everything is as expected 
 
            // We may have 0 or more attachments depending on the file 
            console.log("Document has " + doc.attachments.count + " attachments"); 
 
            // We should have one or more pages unless this is PDF portfolio, then it will have 0 pages 
            if (isPortfolio) { 
               if (doc.pages.count !== 0) throw new Error("Something went wrong"); 
            } 
 
            // Extract all the embedded attachments into the cache 
            this.extractAttachments(doc, 0, () => { 
               console.log("Example done"); 
            }); 
         }); 
      }); 
   } 
 
   loadDocument = (url, loadDocumentOptions, done) => { 
      DocumentHelper.log("Loading document " + url); 
      lt.Document.DocumentFactory.loadFromUri(url, loadDocumentOptions) 
      .done((doc) => { 
         DocumentHelper.log("Document loaded and has cache id: " + doc.documentId); 
         done(doc); 
      }) 
      .fail(DocumentHelper.showServiceError); 
   } 
 
   extractAttachments = (doc, attachmentIndex, done) => { 
      if (attachmentIndex >= doc.attachments.count) { 
         done(); 
         return; 
      } 
 
      // Show info on this attachment 
      const attachment = doc.attachments.item(attachmentIndex); 
      console.log("Attachment number " + attachment.AttachmentNumber + "file name is '" + attachment.fileName +"' and length is " + attachment.fileLength + " bytes"); 
 
      // Save it into the cache 
      // Another option is to load it directly using lt.Document.DocumentFactory.loadDocumentAttachment to load it as a LEAD document 
      const saveAttachmentToCacheOptions = new lt.Document.SaveAttachmentToCacheOptions(); 
      saveAttachmentToCacheOptions.attachmentNumber = attachmentIndex + 1; 
      lt.Document.DocumentFactory.saveAttachmentToCache(doc, null, saveAttachmentToCacheOptions) 
         .done((attachmentDocumentId) => { 
            console.log("attachment " + saveAttachmentToCacheOptions.attachmentNumber + " saved into the cache with document ID = " + attachmentDocumentId); 
 
            // The attachment data can be downloaded using lt.Document.DocumentFactory.downloadDocumentData or loaded using DocumentFactory.loadFromCache 
 
            this.extractAttachments(doc, attachmentIndex + 1, done); 
         }) 
         .fail(DocumentHelper.showServiceError); 
   } 
}

export class DocumentHelper { 
   static showServiceError = (jqXHR, statusText, errorThrown) => { 
      alert("Error returned from service. See the console for details."); 
      const serviceError = lt.Document.ServiceError.parseError(jqXHR, statusText, errorThrown); 
      console.error(serviceError); 
   } 
 
   static log = (message, data) => { 
      const outputElement = document.getElementById("output"); 
      if (outputElement) { 
         const time = (new Date()).toLocaleTimeString(); 
         const textElement = document.createElement("p"); 
         textElement.innerHTML = (outputElement.childElementCount + 1) + " [" + time + "]: " + message; 
         outputElement.insertBefore(textElement, outputElement.firstChild); 
      } 
 
      if (!data) 
         console.log(message); 
      else 
         console.log(message, data); 
   } 
 
   static initFactory = () => { 
      // To communicate with the DocumentsService, it must be running! 
      // Change these parameters to match the path to the service. 
      lt.Document.DocumentFactory.serviceHost = "http://localhost:40000"; 
      lt.Document.DocumentFactory.servicePath = ""; 
      lt.Document.DocumentFactory.serviceApiPath = "api"; 
   } 
}

<!doctype html> 
<html lang="en"> 
<title>Document Example | DocumentAttachment</title> 
 
<head> 
   <script src="https://code.jquery.com/jquery-2.2.4.min.js" 
      integrity="sha256-BbhdlvQf/xTY9gja0Dq3HiwQF8LaCRTXxZKRutelT44=" crossorigin="anonymous"></script> 
 
   <script src="../../LT/Leadtools.js"></script> 
   <script src="../../LT/Leadtools.Controls.js"></script> 
   <script src="../../LT/Leadtools.Annotations.Engine.js"></script> 
   <script src="../../LT/Leadtools.Annotations.Designers.js"></script> 
   <script src="../../LT/Leadtools.Annotations.Rendering.Javascript.js"></script> 
   <script src="../../LT/Leadtools.Annotations.Automation.js"></script> 
   <script src="../../LT/Leadtools.ImageProcessing.Main.js"></script> 
   <script src="../../LT/Leadtools.ImageProcessing.Color.js"></script> 
   <script src="../../LT/Leadtools.ImageProcessing.Core.js"></script> 
   <script src="../../LT/Leadtools.ImageProcessing.Effects.js"></script> 
   <script src="../../LT/Leadtools.Document.js"></script> 
   <script src="../../LT/Leadtools.Document.Viewer.js"></script> 
   <link rel="stylesheet" type="text/css" href="../../css/examples.css"> 
 
   <!-- All demo files are bundled and appended to the window --> 
   <script src="../../bundle.js" type="text/javascript"></script> 
</head> 
 
<body> 
   <div> 
      <button type="button" id="exampleButton">Run Example</button> 
   </div> 
   <div id="output"></div> 
   <div> 
      <img id="img" /> 
   </div> 
</body> 
 
<script> 
   window.onload = () => { 
      const example = new window.examples.DocumentAttachment.Main(); 
      example.run("exampleButton"); 
   }; 
</script> 
</html>

This example will add both a TIF and a PNG document as attachments to a LEADDocument.

DocumentId.ts

DocumentHelper.ts

DocumentId.js

DocumentHelper.js

DocumentId.html

import { DocumentHelper } from "../../utilities/DocumentHelper"; 
 
export class DocumentAttachment_DocumentIdExample { 
   private el: HTMLElement; 
 
   public constructor() { 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
      DocumentHelper.initFactory(); 
   } 
 
   public run(buttonID: string) { 
      document.getElementById(buttonID).onclick = this.onRun; 
   } 
 
   onRun = () => { 
      // Main document 
      const mainDocumentUrl = "https://demo.leadtools.com/images/pdf/leadtools.pdf"; 
      // Attachments 
      const attachmentsUrls = [ 
         "https://demo.leadtools.com/images/png/ocr1.png", 
         "https://demo.leadtools.com/images/tiff/ocr.tif", 
      ]; 
       
      // Load the main document 
      this.loadDocument(mainDocumentUrl, (mainDocument) => { 
         this.showDocumentWithAttachments("Initial", mainDocument, 0, () => { 
 
            // Load all the attachments 
            mainDocument.isReadOnly = false; 
            this.loadAndAddAttachment(mainDocument, attachmentsUrls, 0, () => { 
               mainDocument.isReadOnly = true; 
 
               // Now, show the document info again, it should have 3 attachments 
               this.showDocumentWithAttachments("After adding attachments", mainDocument, attachmentsUrls.length, () => { 
                  // Clean up 
                  lt.Document.DocumentFactory.deleteFromCache(mainDocument.documentId) 
                     .done(() => { 
                        console.log("Example done"); 
                     }) 
                     .fail(DocumentHelper.showServiceError); 
               }); 
            }); 
         }); 
      }); 
   } 
 
   loadDocument = (url: string, done: (doc: lt.Document.LEADDocument) => void) => { 
      DocumentHelper.log("Loading document " + url); 
      lt.Document.DocumentFactory.loadFromUri(url, new lt.Document.LoadDocumentOptions()) 
          .done((doc) => { 
              DocumentHelper.log("Document loaded and has cache id: " + doc.documentId); 
              done(doc); 
          }) 
          .fail(DocumentHelper.showServiceError); 
   } 
 
   showDocumentWithAttachments = (message: string, doc: lt.Document.LEADDocument, attachmentCount: number, done: () => void) => { 
      // Show info about this document and any attachments 
      console.log(message); 
      console.log("  " + this.getDocumentInfo(doc)); 
 
      // Sanity check 
      if (attachmentCount !== doc.attachments.count) throw new Error("Something went wrong"); 
       
      if (doc.attachments.count > 0) { 
         console.log("    attachments:"); 
          
         // Load the attachment documents 
         this.loadAttachmentDocumentsFromCache(doc, 0, done); 
      } else { 
         done(); 
      } 
   } 
 
   loadAndAddAttachment = (mainDocument: lt.Document.LEADDocument, attachmentUrls: string[], attachmentIndex: number, done: () => void) => { 
      if (attachmentIndex >= attachmentUrls.length) { 
         done(); 
         return; 
      } 
 
      console.log("Loading attachment document " + attachmentUrls[attachmentIndex]); 
      this.loadDocument(attachmentUrls[attachmentIndex], (attachmentDocument) => { 
         // Add it to the main document as an attachment 
         const attachment = new lt.Document.DocumentAttachment(); 
         // The attachment number. 
         attachment.attachmentNumber = attachmentIndex + 1; 
         // This is an external attachment 
         attachment.isEmbedded = false; 
         // And the document ID 
         attachment.documentId = attachmentDocument.documentId; 
 
         // The rest of the properties are optional but setting them might be helpful to an application user interface 
         attachment.fileName = attachmentDocument.name; 
         attachment.displayName = attachmentDocument.name; 
         attachment.mimeType = attachmentDocument.mimeType; 
 
         mainDocument.attachments.add(attachment); 
 
         // Load next 
         this.loadAndAddAttachment(mainDocument, attachmentUrls, attachmentIndex + 1, done); 
      }); 
   } 
 
   loadAttachmentDocumentsFromCache = (mainDocument: lt.Document.LEADDocument, attachmentIndex: number, done: () => void) => { 
      if (attachmentIndex >= mainDocument.attachments.count) { 
         done(); 
         return; 
      } 
 
      // Get the attachment document ID 
      const documentAttachment = mainDocument.attachments.item(attachmentIndex); 
      lt.Document.DocumentFactory.loadFromCache(documentAttachment.documentId) 
         .done((doc) => { 
            console.log("    " + this.getDocumentInfo(doc)); 
            this.loadAttachmentDocumentsFromCache(mainDocument, attachmentIndex + 1, done); 
         }) 
         .fail(DocumentHelper.showServiceError); 
   } 
 
   private getDocumentInfo(doc: lt.Document.LEADDocument) { 
      let msg = "documentId:" + doc.documentId; 
      msg += " mimeType:" + doc.mimeType; 
      msg += " pages:" + doc.pages.count; 
      msg += " attachments:" + doc.attachments.count; 
      return msg; 
   } 
}

export class DocumentHelper { 
   static showServiceError = (jqXHR, statusText, errorThrown) => { 
      alert("Error returned from service. See the console for details."); 
      const serviceError = lt.Document.ServiceError.parseError(jqXHR, statusText, errorThrown); 
      console.error(serviceError); 
   } 
 
   static log = (message: string, data?: any) => { 
      const outputElement = document.getElementById("output"); 
      if (outputElement) { 
         const time = (new Date()).toLocaleTimeString(); 
         const textElement = document.createElement("p"); 
         textElement.innerHTML = (outputElement.childElementCount + 1) + " [" + time + "]: " + message; 
         outputElement.insertBefore(textElement, outputElement.firstChild); 
      } 
 
      if (!data) 
         console.log(message); 
      else 
         console.log(message, data); 
   } 
 
   static initFactory = () => { 
      // To communicate with the DocumentsService, it must be running! 
      // Change these parameters to match the path to the service. 
      lt.Document.DocumentFactory.serviceHost = "http://localhost:40000"; 
      lt.Document.DocumentFactory.servicePath = ""; 
      lt.Document.DocumentFactory.serviceApiPath = "api"; 
   } 
}

import { DocumentHelper } from "../../utilities/DocumentHelper"; 
 
export class DocumentAttachment_DocumentIdExample { 
   constructor() { 
      lt.RasterSupport.setLicenseUri("https://demo.leadtools.com/licenses/js/LEADTOOLSEVAL.txt", "EVAL", null); 
      DocumentHelper.initFactory(); 
   } 
 
   run = (buttonID) => { 
      document.getElementById(buttonID).onclick = this.onRun; 
   } 
 
   onRun = () => { 
      // Main document 
      const mainDocumentUrl = "https://demo.leadtools.com/images/pdf/leadtools.pdf"; 
      // Attachments 
      const attachmentsUrls = [ 
         "https://demo.leadtools.com/images/png/ocr1.png", 
         "https://demo.leadtools.com/images/tiff/ocr.tif", 
      ]; 
       
      // Load the main document 
      this.loadDocument(mainDocumentUrl, (mainDocument) => { 
         this.showDocumentWithAttachments("Initial", mainDocument, 0, () => { 
 
            // Load all the attachments 
            mainDocument.isReadOnly = false; 
            this.loadAndAddAttachment(mainDocument, attachmentsUrls, 0, () => { 
               mainDocument.isReadOnly = true; 
 
               // Now, show the document info again, it should have 3 attachments 
               this.showDocumentWithAttachments("After adding attachments", mainDocument, attachmentsUrls.length, () => { 
                  // Clean up 
                  lt.Document.DocumentFactory.deleteFromCache(mainDocument.documentId) 
                     .done(() => { 
                        console.log("Example done"); 
                     }) 
                     .fail(DocumentHelper.showServiceError); 
               }); 
            }); 
         }); 
      }); 
   } 
 
   loadDocument = (url, done) => { 
      DocumentHelper.log("Loading document " + url); 
      lt.Document.DocumentFactory.loadFromUri(url, new lt.Document.LoadDocumentOptions()) 
          .done((doc) => { 
              DocumentHelper.log("Document loaded and has cache id: " + doc.documentId); 
              done(doc); 
          }) 
          .fail(DocumentHelper.showServiceError); 
   } 
 
   showDocumentWithAttachments = (message, doc, attachmentCount, done) => { 
      // Show info about this document and any attachments 
      console.log(message); 
      console.log("  " + this.getDocumentInfo(doc)); 
 
      // Sanity check 
      if (attachmentCount !== doc.attachments.count) throw new Error("Something went wrong"); 
       
      if (doc.attachments.count > 0) { 
         console.log("    attachments:"); 
          
         // Load the attachment documents 
         this.loadAttachmentDocumentsFromCache(doc, 0, done); 
      } else { 
         done(); 
      } 
   } 
 
   loadAndAddAttachment = (mainDocument, attachmentUrls, attachmentIndex, done) => { 
      if (attachmentIndex >= attachmentUrls.length) { 
         done(); 
         return; 
      } 
 
      console.log("Loading attachment document " + attachmentUrls[attachmentIndex]); 
      this.loadDocument(attachmentUrls[attachmentIndex], (attachmentDocument) => { 
         // Add it to the main document as an attachment 
         const attachment = new lt.Document.DocumentAttachment(); 
         // The attachment number. 
         attachment.attachmentNumber = attachmentIndex + 1; 
         // This is an external attachment 
         attachment.isEmbedded = false; 
         // And the document ID 
         attachment.documentId = attachmentDocument.documentId; 
 
         // The rest of the properties are optional but setting them might be helpful to an application user interface 
         attachment.fileName = attachmentDocument.name; 
         attachment.displayName = attachmentDocument.name; 
         attachment.mimeType = attachmentDocument.mimeType; 
 
         mainDocument.attachments.add(attachment); 
 
         // Load next 
         this.loadAndAddAttachment(mainDocument, attachmentUrls, attachmentIndex + 1, done); 
      }); 
   } 
 
   loadAttachmentDocumentsFromCache = (mainDocument, attachmentIndex, done) => { 
      if (attachmentIndex >= mainDocument.attachments.count) { 
         done(); 
         return; 
      } 
 
      // Get the attachment document ID 
      const documentAttachment = mainDocument.attachments.item(attachmentIndex); 
      lt.Document.DocumentFactory.loadFromCache(documentAttachment.documentId) 
         .done((doc) => { 
            console.log("    " + this.getDocumentInfo(doc)); 
            this.loadAttachmentDocumentsFromCache(mainDocument, attachmentIndex + 1, done); 
         }) 
         .fail(DocumentHelper.showServiceError); 
   } 
 
   getDocumentInfo(doc) { 
      let msg = "documentId:" + doc.documentId; 
      msg += " mimeType:" + doc.mimeType; 
      msg += " pages:" + doc.pages.count; 
      msg += " attachments:" + doc.attachments.count; 
      return msg; 
   } 
}

export class DocumentHelper { 
   static showServiceError = (jqXHR, statusText, errorThrown) => { 
      alert("Error returned from service. See the console for details."); 
      const serviceError = lt.Document.ServiceError.parseError(jqXHR, statusText, errorThrown); 
      console.error(serviceError); 
   } 
 
   static log = (message, data) => { 
      const outputElement = document.getElementById("output"); 
      if (outputElement) { 
         const time = (new Date()).toLocaleTimeString(); 
         const textElement = document.createElement("p"); 
         textElement.innerHTML = (outputElement.childElementCount + 1) + " [" + time + "]: " + message; 
         outputElement.insertBefore(textElement, outputElement.firstChild); 
      } 
 
      if (!data) 
         console.log(message); 
      else 
         console.log(message, data); 
   } 
 
   static initFactory = () => { 
      // To communicate with the DocumentsService, it must be running! 
      // Change these parameters to match the path to the service. 
      lt.Document.DocumentFactory.serviceHost = "http://localhost:40000"; 
      lt.Document.DocumentFactory.servicePath = ""; 
      lt.Document.DocumentFactory.serviceApiPath = "api"; 
   } 
}

<!doctype html> 
<html lang="en"> 
<title>Document Example | DocumentAttachment.DocumentID</title> 
 
<head> 
   <script src="https://code.jquery.com/jquery-2.2.4.min.js" 
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