Node.js+web TWAIN for Web document scanning and image uploading

With a combination of the dynamic Web TWAIN SDK and node. js, only a few lines of code can be implemented to control the scanner in the browser, get the image and upload it to the remote server.

Original:Document Imaging and uploading with Dynamic Web TWAIN and node. js

Download installation

• Dynamic Web TWAIN Download

• node. js Download

Creating a server from node. js

Create a Project catalog, open cmd.exe into the project catalog, install the following two node. js Modules:

NPM Install [email protected]npm install Express

Create Server.js, Initialize:

var formidable = require (' formidable '); var util = require (' util '); var express = require (' Express '); var fs = require (' FS '); var app = Express ();

The static resources, compared to slices, CSS, etc., are loaded in:

App.use (Express.static (__dirname, '/public '));

To achieve cross-domain access, you need to add permissions to the header and, if not added, only local access:

App.use (function (req, res, next) {Res.header ("Access-control-allow-origin", "*");      Res.header ("Access-control-allow-methods", "PUT, POST, GET, DELETE, OPTIONS");      Res.header ("Access-control-allow-headers", "X-requested-with, Content-type");      Res.header ("Access-control-allow-credentials", true);  Next (); });

Parse the data through formidable in the POST request:

App.post ('/upload ',  function (req, res)  {    var form = new  formidable. Incomingform ();     form.parse (Req, function (err, fields, files)  {         // console.log (Util.inspect ({         //     fields: fields,         //     files: files         // });          fs.readfile (Files. Remotefile.path, function (Err, data)  {             // save file from temp dir to new dir             var newpath = __dirname +   "/uploads/"  + files. RemoTefile.name;            fs.writefile (NewPath,  data, function (ERR)  {                 if  (ERR)  throw err;                 console.log (' file saved ');                   res.end ();             });         }); (    });})

Set the IP and port:

var server = App.listen, function () {var host = Server.address (). Address;    var port = server.address (). Port; Console.log (' Listening at http://%s:%s ', host, Port);})

Creating a client with dynamic WEB TWAIN

Create a Web page that contains a div and two buttons:

  
A copy of the resources directory under the Web TWAIN SDK installation directory is required here.
 
Add a few lines of code to scan:
 
function Acquireimage () {Dwobject.ifshowui = false;     Dwobject.selectsource ();     Dwobject.opensource (); Dwobject.acquireimage ();}
  
Here you can test whether the scan is working properly. Next, implement remote uploads:
 
Function btnupload_onclick ()  {       dwobject.httpport =  2014;       var currentpathname = unescape ( Location.pathname); // get current pathname in plain ascii        var currentpath = currentpathname.substring (0,  Currentpathname.lastindexof ("/")  + 1);       var  stractionpage = currentpath +  "Upload";       var  strhostip =  "localhost";  // modify the ip for cross-domain access        var sfun = function () {            alert (' successful ');        }, ffun  = function () {     &Nbsp;     alert (' failed ');       };        dwobject.httpuploadthroughpostex (        strhostip,       dwobject.currentimageindexinbuffer,        strActionPage,        "Test.jpg",        1,// JPEG       sFun, fFun        );}
  
Under test. Command line Start server:
 
Node Server.js
  
Open the http://localhost:2014 and you can play.
 Source
 
Https://github.com/DynamsoftRD/nodejs-dwt
 
git clone https://github.com/DynamsoftRD/nodejs-dwt.git
  

Node.js+web TWAIN for Web document scanning and image uploading