Node.js - escape HTML special characters

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// Note: in this snippet you can find quite optimal solution to escape HTML special characters.

// Hint: you can try to speed up source code much more by updating `escapeHtml()` function.
//
//       from:
//       ```
//           for (const character of html) {
//               ...
//       ```
//
//       to:
//       ```
//           for (let i = 0; i < html.length; ++i) {
//               const character = html[i];
//               ...
//       ```


const escapeHtml = (html) => {
    let result = '';
    for (const character of html) {
        switch (character) {
            // Warning: do not change cases order
            case '&':  result += '&amp;';  break;
            case '<':  result += '&lt;';   break;
            case '>':  result += '&gt;';   break;
            case '"':  result += '&quot;'; break;
            case '\'': result += '&#039;'; break;
            default:   result += character;
        }
    }
    return result;
};


// Usage example:

console.log(escapeHtml('<div class="message">Hi!</div>'));  // &lt;div class=&quot;message&quot;&gt;Hi!&lt;/div&gt;


// Output:
//
//     &lt;div class=&quot;message&quot;&gt;Hi!&lt;/div&gt;


// See also:
//
//     1. https://dirask.com/snippets/Node-js-escape-HTML-special-characters-DKgEnD