How to Extract Text from a PDF in JavaScript

Extract text from pdf file using javascript

here is a nice example of how to use pdf.js for extracting the text:
http://git.macropus.org/2011/11/pdftotext/example/

of course you have to remove a lot of code for your purpose, but it should do it

How to extract text from a PDF in JavaScript

Because pdf.js has been developing over the years, I would like to give a new answer. That is, it can be done locally without involving any server or external service. The new pdf.js has a function: page.getTextContent(). You can get the text content from that. I've done it successfully with the following code.

What you get in each step is a promise. You need to code this way: .then( function(){...}) to proceed to the next step.

PDFJS.getDocument( data ).then( function(pdf) {
pdf.getPage(i).then( function(page){
page.getTextContent().then( function(textContent){

What you finally get is an string array textContent.bidiTexts[]. You concatenate them to get the text of 1 page. Text blocks' coordinates are used to judge whether newline or space need to be inserted. (This may not be totally robust, but from my test it seems ok.)
The input parameter data needs to be either a URL or ArrayBuffer type data. I used the ReadAsArrayBuffer(file) function in FileReader API to get the data.

Note: According to some other user, the library has updated and caused the code to break. According to the comment by async5 below, you need to replace textContent.bidiTexts with textContent.items.

    function Pdf2TextClass(){
     var self = this;
     this.complete = 0;

    /**
     *
     * @param data ArrayBuffer of the pdf file content
     * @param callbackPageDone To inform the progress each time
     *        when a page is finished. The callback function's input parameters are:
     *        1) number of pages done;
     *        2) total number of pages in file.
     * @param callbackAllDone The input parameter of callback function is 
     *        the result of extracted text from pdf file.
     *
     */
     this.pdfToText = function(data, callbackPageDone, callbackAllDone){
     console.assert( data  instanceof ArrayBuffer  || typeof data == 'string' );
     PDFJS.getDocument( data ).then( function(pdf) {
     var div = document.getElementById('viewer');
    
     var total = pdf.numPages;
     callbackPageDone( 0, total );        
     var layers = {};        
     for (i = 1; i <= total; i++){
        pdf.getPage(i).then( function(page){
        var n = page.pageNumber;
        page.getTextContent().then( function(textContent){
          if( null != textContent.bidiTexts ){
            var page_text = "";
            var last_block = null;
            for( var k = 0; k < textContent.bidiTexts.length; k++ ){
                var block = textContent.bidiTexts[k];
                if( last_block != null && last_block.str[last_block.str.length-1] != ' '){
                    if( block.x < last_block.x )
                        page_text += "\r\n"; 
                    else if ( last_block.y != block.y && ( last_block.str.match(/^(\s?[a-zA-Z])$|^(.+\s[a-zA-Z])$/) == null ))
                        page_text += ' ';
                }
                page_text += block.str;
                last_block = block;
            }

            textContent != null && console.log("page " + n + " finished."); //" content: \n" + page_text);
            layers[n] =  page_text + "\n\n";
          }
          ++ self.complete;
          callbackPageDone( self.complete, total );
          if (self.complete == total){
            window.setTimeout(function(){
              var full_text = "";
              var num_pages = Object.keys(layers).length;
              for( var j = 1; j <= num_pages; j++)
                  full_text += layers[j] ;
              callbackAllDone(full_text);
            }, 1000);              
          }
        }); // end  of page.getTextContent().then
      }); // end of page.then
    } // of for
  });
 }; // end of pdfToText()
}; // end of class

How to correctly extract text from a pdf using pdf.js

Similar to https://stackoverflow.com/a/40494019/1765767 -- collect page promises using Promise.all and don't forget to chain then's:

function gettext(pdfUrl){
  var pdf = pdfjsLib.getDocument(pdfUrl);
  return pdf.then(function(pdf) { // get all pages text
    var maxPages = pdf.pdfInfo.numPages;
    var countPromises = []; // collecting all page promises
    for (var j = 1; j <= maxPages; j++) {
      var page = pdf.getPage(j);

      var txt = "";
      countPromises.push(page.then(function(page) { // add page promise
        var textContent = page.getTextContent();
        return textContent.then(function(text){ // return content promise
          return text.items.map(function (s) { return s.str; }).join(''); // value page text 
        });
      }));
    }
    // Wait for all pages and join text
    return Promise.all(countPromises).then(function (texts) {
      return texts.join('');
    });
  });
}

// waiting on gettext to finish completion, or error
gettext("https://cdn.mozilla.net/pdfjs/tracemonkey.pdf").then(function (text) {
  alert('parse ' + text);
}, 
function (reason) {
  console.error(reason);
});

<script src="https://npmcdn.com/pdfjs-dist/build/pdf.js"></script>

How to extract text from a pdf file in javascript?

PDF.js allows you to load file objects and then parse the document as a text. This example from the official website does exactly that.

How to extract text from PDF?

I'm answering my own question. First I create a regular html input.

<input type='file'/>

I'm using React, so I use onChange attribute in place of id.
So, when the user enters with the file, a function is activated and I use the following code to get the file:

const file = event.target.files[0];

file not has a path, which is used by PDF.JS to get the real file.
Then I use a FileReader to convert the file int a Array of bits (I guess):

const fileReader = new FileReader();

Then we set a function at fileReader.onload the function can be found here

fileReader.onload = function() {...}

Finally we do this:

fileReader.readAsArrayBuffer(file);

Important PS: pdf.pdfInfo must be replaced with pdf at new PDF.JS versions.

Thanks for helping.

Extra PS: To use pdfjsLib as PDFJS in React I did this in index.html file:

window.PDFJS = pdfjsLib

Extract specific portion of text from pdf using Javascript?

You could match Datacover between word boundaries \b and repeat in a non greedy way 3 times matching any char including a newling [\s\S]*? until the next occurrence of a dot and space \.

\bDatacover\b(?:[\s\S]*?\. ){3}

Regex demo

To get the data, you could use

event.data.match(regex)

For example:

const regex = /\bDatacover\b(?:[\s\S]*?\. ){3}/g;let event = {  data: `testhjgjhg hjg jhg jkgh kjhghjkg76t 76 tguygtf yr 6 rt6 gtyut 67 tuy yoty yutyu tyu yutyuit iyut iuytiyu tuiyt Datacover uytuy tuyt uyt uiytuiyt uytutest.yu tuyt uyt uyt iutiuyt uiy yuitui tuyttest.  uiyt uiytuiyt uyt ut uithis is a test. sjhdgfjsa. hgwryuehrgfhrghw fsdfdfsfs sddsfdfs.`};
console.log(event.data.match(regex));