Pdf js rendering a pdf file using a base64 file source instead of url

Question

I m trying to render a page from a pdf with pdf js  Normally  using a url  I can do this   PDFJS getDocument  http   www server com file pdf   then function getPdfHelloWorld pdf              Fetch the first page        pdf getPage 1  then function getPageHelloWorld page        var scale   1 5      var viewport   page getViewport scale                  Prepare canvas using PDF page dimensions            var canvas   document getElementById  the-canvas        var context   canvas getContext  2d        canvas height   viewport height      canvas width   viewport width                 Render PDF page into canvas context            page render  canvasContext  context  viewport  viewport                But in this case  I have the file in base64 rather than an url   data application pdf base64 JVBERi0xLjUKJdDUxdgKNSAwIG9iaiA8PAovTGVuZ3RoIDE2NjUgICAgICAKL0ZpbHRlciAvRmxhdGVEZWNvZGUKPj4Kc3RyZWFtCnjarVhLc9s2      How this can be done

User · Answer

According to the examples base64 encoding is directly supported  although I ve not tested it myself  Take your base64 string  derived from a file or loaded with any other method  POST GET  websockets etc   turn it to a binary with atob  and then parse this to getDocument on the PDFJS API likePDFJS getDocument  data  base64PdfData    Codetoffel answer does work just fine for me though

User · Answer

from the sourcecode at http   mozilla github com pdf js build pdf js         This is the main entry point for loading a PDF and interacting with it     NOTE  If a URL is used to fetch the PDF data a standard XMLHttpRequest XHR     is used  which means it must follow the same origin rules that any XHR does    e g  No cross domain requests without CORS         param  string TypedAray object  source Can be an url to where a PDF is    located  a typed array  Uint8Array  already populated with data or    and parameter object with the following possible fields      - url   - The URL of the PDF      - data  - A typed array with PDF data      - httpHeaders - Basic authentication headers      - password - For decrypting password-protected PDFs         return  Promise  A promise that is resolved with  PDFDocumentProxy  object        So a standard XMLHttpRequest XHR  is used for retrieving the document   The Problem with this is that XMLHttpRequests do not support data  uris  eg  data application pdf base64 JVBERi0xLjUK       But there is the possibility of passing a typed Javascript Array to the function  The only thing you need to do is to convert the base64 string to a Uint8Array  You can use this function found at https   gist github com 1032746  var BASE64 MARKER     base64     function convertDataURIToBinary dataURI      var base64Index   dataURI indexOf BASE64 MARKER    BASE64 MARKER length    var base64   dataURI substring base64Index     var raw   window atob base64     var rawLength   raw length    var array   new Uint8Array new ArrayBuffer rawLength       for var i   0  i  lt  rawLength  i          array i    raw charCodeAt i         return array      tl dr  var pdfAsDataUri    data application pdf base64 JVBERi0xLjUK         shortened var pdfAsArray   convertDataURIToBinary pdfAsDataUri   PDFJS getDocument pdfAsArray

User · Answer

Used the Accepted Answer to do a check for IE and convert the dataURI to UInt8Array  an accepted form by PDFJS  x000D   x000D          Ext isIE   pdfAsDataUri   me convertDataURIToBinary pdfAsDataUri       x000D   x000D          convertDataURIToBinary  function dataURI    x000D            var BASE64 MARKER     base64    x000D              base64Index   dataURI indexOf BASE64 MARKER    BASE64 MARKER length  x000D              base64   dataURI substring base64Index   x000D              raw   window atob base64   x000D              rawLength   raw length  x000D              array   new Uint8Array new ArrayBuffer rawLength    x000D   x000D            for  var i   0  i  lt  rawLength  i      x000D              array i    raw charCodeAt i   x000D              x000D            return array  x000D             x000D   x000D   x000D

[javascript] Pdf.js: rendering a pdf file using a base64 file source instead of url

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