JavaScript sets and value objects [duplicate]

问题

This question already has answers here:

user defined object equality for a set in harmony (es6) (2 answers)

Closed 4 years ago.

I want to create a set of value objects in JavaScript. The problem is that in JavaScript equality is based on identity. Hence, two different objects with the same value will be treated as unequal:

var objects = new Set;

objects.add({ a: 1 });
objects.add({ a: 1 });

alert(objects.size);   // expected 1, actual 2

How do you work around this problem?

回答1:

Use JSON.stringify:

var objects = new Set;

objects.add(JSON.stringify({ a: 1 }));
objects.add(JSON.stringify({ a: 1 }));

alert(objects.size);

来源：https://stackoverflow.com/questions/29272134/javascript-sets-and-value-objects