xsheetjs/docbits/20_import.md
Jimmy Wärting ca22658b8c README use typed array (fixes #1362)
> The use of readAsArrayBuffer() is preferred over readAsBinaryString(),
> which is provided for backwards compatibility.
2019-04-01 09:33:51 -04:00

4.8 KiB

Parsing Workbooks

For parsing, the first step is to read the file. This involves acquiring the data and feeding it into the library. Here are a few common scenarios:

nodejs read a file (click to show)

readFile is only available in server environments. Browsers have no API for reading arbitrary files given a path, so another strategy must be used.

if(typeof require !== 'undefined') XLSX = require('xlsx');
var workbook = XLSX.readFile('test.xlsx');
/* DO SOMETHING WITH workbook HERE */
Photoshop ExtendScript read a file (click to show)

readFile wraps the File logic in Photoshop and other ExtendScript targets. The specified path should be an absolute path:

#include "xlsx.extendscript.js"
/* Read test.xlsx from the Documents folder */
var workbook = XLSX.readFile(Folder.myDocuments + '/' + 'test.xlsx');
/* DO SOMETHING WITH workbook HERE */

The extendscript demo includes a more complex example.

Browser read TABLE element from page (click to show)

The table_to_book and table_to_sheet utility functions take a DOM TABLE element and iterate through the child nodes.

var workbook = XLSX.utils.table_to_book(document.getElementById('tableau'));
/* DO SOMETHING WITH workbook HERE */

Multiple tables on a web page can be converted to individual worksheets:

/* create new workbook */
var workbook = XLSX.utils.book_new();

/* convert table 'table1' to worksheet named "Sheet1" */
var ws1 = XLSX.utils.table_to_sheet(document.getElementById('table1'));
XLSX.utils.book_append_sheet(workbook, ws1, "Sheet1");

/* convert table 'table2' to worksheet named "Sheet2" */
var ws2 = XLSX.utils.table_to_sheet(document.getElementById('table2'));
XLSX.utils.book_append_sheet(workbook, ws2, "Sheet2");

/* workbook now has 2 worksheets */

Alternatively, the HTML code can be extracted and parsed:

var htmlstr = document.getElementById('tableau').outerHTML;
var workbook = XLSX.read(htmlstr, {type:'string'});
Browser download file (ajax) (click to show)

Note: for a more complete example that works in older browsers, check the demo at http://oss.sheetjs.com/js-xlsx/ajax.html. The xhr demo includes more examples with XMLHttpRequest and fetch.

var url = "http://oss.sheetjs.com/test_files/formula_stress_test.xlsx";

/* set up async GET request */
var req = new XMLHttpRequest();
req.open("GET", url, true);
req.responseType = "arraybuffer";

req.onload = function(e) {
  var data = new Uint8Array(req.response);
  var workbook = XLSX.read(data, {type:"array"});

  /* DO SOMETHING WITH workbook HERE */
}

req.send();
Browser drag-and-drop (click to show)

Drag-and-drop uses the HTML5 FileReader API.

function handleDrop(e) {
  e.stopPropagation(); e.preventDefault();
  var files = e.dataTransfer.files, f = files[0];
  var reader = new FileReader();
  reader.onload = function(e) {
    var data = new Uint8Array(e.target.result);
    var workbook = XLSX.read(data, {type: 'array'});

    /* DO SOMETHING WITH workbook HERE */
  };
  reader.readAsArrayBuffer(f);
}
drop_dom_element.addEventListener('drop', handleDrop, false);
Browser file upload form element (click to show)

Data from file input elements can be processed using the same FileReader API as in the drag-and-drop example:

function handleFile(e) {
  var files = e.target.files, f = files[0];
  var reader = new FileReader();
  reader.onload = function(e) {
    var data = new Uint8Array(e.target.result);
    var workbook = XLSX.read(data, {type: 'array'});

    /* DO SOMETHING WITH workbook HERE */
  };
  reader.readAsArrayBuffer(f);
}
input_dom_element.addEventListener('change', handleFile, false);

The oldie demo shows an IE-compatible fallback scenario.

More specialized cases, including mobile app file processing, are covered in the included demos

Parsing Examples

Note that older versions of IE do not support HTML5 File API, so the Base64 mode is used for testing.

Get Base64 encoding on OSX / Windows (click to show)

On OSX you can get the Base64 encoding with:

$ <target_file base64 | pbcopy

On Windows XP and up you can get the Base64 encoding using certutil:

> certutil -encode target_file target_file.b64

(note: You have to open the file and remove the header and footer lines)