xsheetjs/demos/react/README.md

React

The xlsx.core.min.js and xlsx.full.min.js scripts are designed to be dropped into web pages with script tags:

<script src="xlsx.full.min.js"></script>

The library can also be imported directly from JSX code with:

import { read, utils, writeFileXLSX } from 'xlsx';

This demo shows a simple React component transpiled in the browser using Babel standalone library. Since there is no standard React table model, this demo settles on the array of arrays approach.

Other scripts in this demo show:

• server-rendered React component (with next.js)
• react-native deployment for iOS and android
• react-data-grid reading, modifying, and writing files

How to run

Run make react to run the browser demo for React, or run make next to run the server-rendered demo using next.js.

Internal State

The simplest state representation is an array of arrays. To avoid having the table component depend on the library, the column labels are precomputed. The state in this demo is shaped like the following object:

{
  cols: [{ name: "A", key: 0 }, { name: "B", key: 1 }, { name: "C", key: 2 }],
  data: [
    [ "id",    "name", "value" ],
    [    1, "sheetjs",    7262 ],
    [    2, "js-xlsx",    6969 ]
  ]
}

sheet_to_json and aoa_to_sheet utility functions can convert between arrays of arrays and worksheets:

/* convert from workbook to array of arrays */
var first_worksheet = workbook.Sheets[workbook.SheetNames[0]];
var data = XLSX.utils.sheet_to_json(first_worksheet, {header:1});

/* convert from array of arrays to workbook */
var worksheet = XLSX.utils.aoa_to_sheet(data);
var new_workbook = XLSX.utils.book_new();
XLSX.utils.book_append_sheet(new_workbook, worksheet, "SheetJS");

The column objects can be generated with the encode_col utility function:

function make_cols(refstr/*:string*/) {
  var o = [];
  var range = XLSX.utils.decode_range(refstr);
  for(var i = 0; i <= range.e.c; ++i) {
    o.push({name: XLSX.utils.encode_col(i), key:i});
  }
  return o;
}

React Native

Reproducing the full project is straightforward:

$ make native     # build the project
$ make ios        # build and run the iOS demo
$ make android    # build and run the android demo

The app will prompt before reading and after writing data. The printed location depends on the environment:

• android: path in the device filesystem
• iOS simulator: local path to file
• iOS device: a path accessible from iTunes App Documents view

Components used in the demo:

• react-native-table-component
• react-native-file-access

React Native does not provide a native component for reading and writing files. The sample script <react-native.js> uses react-native-file-access and has notes for integrations with react-native-fetch-blob and react-native-fs.

Note: for real app deployments, the UIFileSharingEnabled flag must be manually set in the iOS project Info.plist file.

Server-Rendered React Components with Next.js

The demo uses the same component code as the in-browser version, but the build step adds a small header that imports the library. The import is not needed in deployments that use script tags to include the library.

Additional Notes

Some additional notes can be found in NOTES.md.