JavaScript 深度克隆

function clone(obj) {
    var copy;

    // Handle the 3 simple types, and null or undefined
    if (null == obj || "object" != typeof obj) return obj;

    // Handle Date
    if (obj instanceof Date) {
        copy = new Date();
        copy.setTime(obj.getTime());
        return copy;
    }

    // Handle Array
    if (obj instanceof Array) {
        copy = [];
        for (var i = 0, len = obj.length; i < len; i++) {
            copy[i] = clone(obj[i]);
        }
        return copy;
    }

    // Handle Object
    if (obj instanceof Object) {
        copy = {};
        for (var attr in obj) {
            if (obj.hasOwnProperty(attr)) copy[attr] = clone(obj[attr]);
        }
        return copy;
    }

    throw new Error("Unable to copy obj! Its type isn't supported.");
}

Object.assign

The Object.assign() method is used to copy the values of all enumerable own properties from one or more source objects to a target object. It will return the target object.

Object.assign(target, ...sources)

But be aware that this makes a shallow copy only. Nested objects are still copied as references! 浅拷贝

How do I correctly clone a JavaScript object?