Handsontable with TypeScript: A Comprehensive Guide

Table of Contents#

1. Fundamental Concepts
2. Installation and Setup
3. Basic Usage
4. Common Practices
5. Best Practices
6. Conclusion
7. References

Fundamental Concepts#

Handsontable#

Handsontable is a data grid component that mimics the look and feel of a spreadsheet. It allows users to display, edit, and manipulate tabular data in a web - based environment. It supports various data types, cell formatting, and events.

TypeScript#

TypeScript is a superset of JavaScript that adds static typing. By using types, TypeScript helps developers catch errors at compile - time rather than runtime. When using Handsontable with TypeScript, we can define types for the data, configurations, and events of Handsontable, making the code more robust and easier to understand.

Handsontable with TypeScript#

When using Handsontable with TypeScript, we can take advantage of type definitions provided by Handsontable. These type definitions help us write code that is more type - safe and easier to refactor. For example, we can define the type of the data source, the type of cell editors, and the type of event handlers.

Installation and Setup#

Prerequisites#

• Node.js and npm (Node Package Manager) installed on your machine.

Step 1: Create a new TypeScript project#

mkdir handsontable-ts-project
cd handsontable-ts-project
npm init -y

Step 2: Install Handsontable and its TypeScript definitions#

npm install handsontable
npm install @handsontable/react @types/handsontable --save-dev

Step 3: Configure TypeScript#

Create a tsconfig.json file in the root of your project with the following basic configuration:

{
  "compilerOptions": {
    "target": "ES6",
    "module": "commonjs",
    "strict": true,
    "esModuleInterop": true,
    "skipLibCheck": true,
    "forceConsistentCasingInFileNames": true
  }
}

Basic Usage#

Importing Handsontable#

First, import the necessary modules in your TypeScript file.

import Handsontable from 'handsontable/base';
import 'handsontable/dist/handsontable.full.min.css';
 
// Create a container for the Handsontable
const container = document.createElement('div');
document.body.appendChild(container);
 
// Define the data source
const data = [
  ['', 'Tesla', 'Volvo', 'Toyota', 'Ford'],
  ['2019', 10, 11, 12, 13],
  ['2020', 20, 11, 14, 13],
  ['2021', 30, 15, 12, 13]
];
 
// Define the Handsontable settings
const hotSettings: Handsontable.GridSettings = {
  data: data,
  colHeaders: true,
  rowHeaders: true
};
 
// Initialize the Handsontable instance
const hot = new Handsontable(container, hotSettings);

In the above code:

1. We first import the Handsontable base module and its CSS file.
2. Then we create a div element as the container for the Handsontable.
3. We define a two - dimensional array data as the data source for the table.
4. We set up the hotSettings object with some basic configurations like colHeaders and rowHeaders.
5. Finally, we initialize the Handsontable instance with the container and the settings.

Common Practices#

Data Manipulation#

Handsontable provides methods to manipulate data easily. For example, to get the data from the table:

const newData = hot.getData();
console.log(newData);

To set new data:

const newDataSource = [
  ['', 'BMW', 'Audi', 'Mercedes'],
  ['2022', 15, 16, 17]
];
hot.loadData(newDataSource);

Cell Formatting#

You can format cells in Handsontable using the columns option in the settings. For example, to format a column as a currency:

const hotSettings: Handsontable.GridSettings = {
  data: data,
  colHeaders: true,
  rowHeaders: true,
  columns: [
    {
      data: 1,
      type: 'numeric',
      numericFormat: {
        pattern: '$ 0,0.00'
      }
    }
  ]
};

Event Handling#

Handsontable emits various events that you can listen to. For example, to listen to the afterChange event:

const hotSettings: Handsontable.GridSettings = {
  data: data,
  colHeaders: true,
  rowHeaders: true,
  afterChange: (changes, source) => {
    if (source!== 'loadData') {
      console.log('Data has been changed:', changes);
    }
  }
};

Best Practices#

Typing the Data Source#

When using TypeScript, it's a good practice to define the type of the data source. For example, if our data represents sales data with a year and a number of sales:

type SalesData = [string, number];
const data: SalesData[] = [
  ['2019', 100],
  ['2020', 120]
];
 
const hotSettings: Handsontable.GridSettings = {
  data: data,
  colHeaders: ['Year', 'Sales'],
  rowHeaders: true
};

Code Organization#

Separate the configuration and initialization of Handsontable into different functions. This makes the code more modular and easier to maintain.

function createHandsontableContainer() {
  const container = document.createElement('div');
  document.body.appendChild(container);
  return container;
}
 
function getHandsontableSettings(data: any) {
  return {
    data: data,
    colHeaders: true,
    rowHeaders: true
  };
}
 
const container = createHandsontableContainer();
const settings = getHandsontableSettings(data);
const hot = new Handsontable(container, settings);

Error Handling#

When working with Handsontable, it's important to handle potential errors gracefully. For example, when initializing Handsontable, check if the container element exists:

const container = document.getElementById('hot-container');
if (container) {
  const hot = new Handsontable(container, hotSettings);
} else {
  console.error('Handsontable container element not found.');
}

Conclusion#

Handsontable with TypeScript offers a powerful and type - safe solution for creating spreadsheet - like data grids in web applications. By understanding the fundamental concepts, following the installation and setup steps, and applying common and best practices, developers can efficiently use Handsontable to build feature - rich data grids. The combination of Handsontable's flexibility and TypeScript's static typing helps in writing more reliable and maintainable code.

References#

• Handsontable official documentation
• TypeScript official documentation
• MDN Web Docs for JavaScript