javascript check value of each object key code example

Example 1: how to check if object has key javascript

myObj.hasOwnProperty('key') // it checks object for particular key and not on prototype

Example 2: js check if object key exists

var obj = { key: undefined };
obj["key"] !== undefined // false, but the key exists!

Example 3: javascript object get value by key

var obj = {
   a: "A",
   b: "B",
   c: "C"
}

console.log(obj.a);  // return string : A

var name = "a";
console.log(obj[name]);