js convert string to utf8

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// Note: Almost all JavaScript engines by default store string literals using UTF-16 encoding format.
//       By using the below function we do conversion from default encoding to UTF-8 encoding.

function toUtf8(text) {
    var result = '';
    for (var i = 0; i < text.length; i++) {
        var code = text.charCodeAt(i);
        if (code < 0x80) {
            result += String.fromCharCode(code);
        } else {
            if (code < 0x800) {
                result += String.fromCharCode(code >> 6 & 0x1F | 0xC0);
            } else {
                result += String.fromCharCode(code >> 12 | 0xE0);
                result += String.fromCharCode(code >> 6 & 0x3F | 0x80);
            }
            result += String.fromCharCode(code & 0x3F | 0x80);
        }
    }
    return result;
}


// Usage example:

const utf16Text = 'I ❤️ JS';          // I ❤️ JS
const utf8Text = toUtf8(utf16Text);  // I ❤️ JS

console.log(utf8Text);  // I ❤️ JS


// See also:
//   https://dirask.com/questions/What-encoding-uses-JavaScript-to-stores-string-jM73zD