What is the JavaScript equivalent to a C# HashSet?

Question

I have a list of a few thousand integer keys. The only thing I need to do with this list is say whether or not a given value is in the list.

For C# I would use a

Answer 1

You can use just a regular JavaScript object and the 'in' keyword to see if that object has a certain key.

var myObj = {
  name: true,
  age: true
}

'name' in myObj //returns true;
'height' in myObj // returns false;

Or if you know you're going to have keys in your object that might be built in JavaScript object properties use...

var myObj = {
  name: true,
  age: true
}

myObj.hasOwnProperty('name') //returns true;
myObj.hasOwnProperty('height') // returns false;