javascript check if key exist in object 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: javascript hashtable contains key

if (obj.hasOwnProperty("key1")) {
  ...
}

Example 3: check if a key exists in an object javascript

"key" in obj // true, regardless of the actual value