Javascript Check if Key Exists (Exact Code That Works)

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Javascript Check if Key Exists (Exact Code That Works)
OUTLINE:
00:00:00 Introduction to JavaScript Objects
00:00:18 Methods of Key Verification
00:01:02 Cautionary Note on Key Values
Here is the code written out for you:
Methods of Exploration
The 'in' Operator: This nimble tool returns 'true' if your key dwells within the object or its prototype chain. It's like a swift scout venturing into the object's territory.
const treasureChest = { gold: 100, map: true };
if ('gems' in treasureChest) {
console.log("Aha! Gems are found!");
}
The 'hasOwnProperty()' Method: This method is more meticulous. It returns 'true' only if the key exists directly on the object, ignoring its ancestors in the prototype chain. Think of it as a focused inspector checking only the top layer.