In JavaScript, you can check if an object has a specific property using various methods, such as the hasOwnProperty() method, the in operator, or using the Object.keys() method.
Here’s how you can achieve it using these methods:
Using the hasOwnProperty() method
The hasOwnProperty() method checks if an object has a property with the specified name. It returns true if the object has the property directly on itself (not inherited from its prototype chain), otherwise it returns false .
const obj = { name: "John", age: 30 };
console.log(obj.hasOwnProperty("name")); // Output: true console.log(obj.hasOwnProperty("gender")); // Output: false
Using the in operator
The in operator checks if an object has a property with the specified name, including properties inherited from its prototype chain. It returns true if the property exists, otherwise it returns false .
const obj = { name: "John", age: 30 };
console.log("name" in obj); // Output: true console.log("gender" in obj); // Output: false
Using the Object.keys() method
The Object.keys() method returns an array of a given object’s own enumerable property names. You can then check if the property exists by searching for its name in the array.
const obj = { name: "John", age: 30 };
console.log(Object.keys(obj).includes("name")); // Output: true console.log(Object.keys(obj).includes("gender")); // Output: false
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