JSON.parse() Reviving Class Example

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<h2>Parsing and Restoring Custom Class Instances</h2>
		<p>Click below to parse JSON that represents a <code>Point</code> object and restore it as an actual class instance using a <code>reviver</code> function.</p>

<button onclick="loadPoint()">Parse Point</button>

<div class="user-card" id="pointCard">
			<h3>Point Instance</h3>
			<p><strong>X:</strong> <span id="xValue"></span></p>
			<p><strong>Y:</strong> <span id="yValue"></span></p>
			<p><strong>Is Point Instance:</strong> <span id="isInstance"></span></p>
		</div>

function loadPoint() {
				const json = '{"__type":"Point","x":10,"y":20}';

const point = JSON.parse(json, (key, value) => {
					if (value && value.__type === "Point") {
						return new Point(value.x, value.y);
					}
					return value;
				});

document.getElementById('xValue').textContent = point.x;
				document.getElementById('yValue').textContent = point.y;
				document.getElementById('isInstance').textContent = point instanceof Point ? 'Yes' : 'No';
				document.getElementById('pointCard').style.display = 'block';
			}
		</script>

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