文字列を使用してネストされた JavaScript オブジェクトのプロパティにアクセスする方法

var r = { a: 1, b: { b1: 11, b2: 99 } };

r.b.b2

var s = "b.b2";

function getDescendantProp(obj, desc) {
  var arr = desc.split(".");
  while (arr.length && (obj = obj[arr.shift()]));
  return obj;
}

console.log(getDescendantProp(r, "b.b2")); // 99
````

This function effectively simulates the behavior of dot notation by breaking down the string and recursively accessing the corresponding properties. However, it is important to note that this method works best for simple object property scenarios. Arrays can also be accessed using this approach by treating elements as dotted properties: