如何在不知道 JavaScript 物件名稱的情況下存取其第一個屬性？

Accessing the First Property of a JavaScript Object Without Knowing Its Name

In JavaScript, there are scenarios where you need to access the first property of an object without prior knowledge of its name. This can be a challenge, especially if you want to do it efficiently and elegantly.

Two methods can effectively achieve this task:

1. Using Object.keys() and Index Access:

var obj = { first: 'someVal' };
obj[Object.keys(obj)[0]]; //returns 'someVal'

Here, Object.keys() creates an array of property names, and you can access the first property using an index.

2. Using Object.values() and Index Access:

Object.values(obj)[0]; // returns 'someVal'

Object.values() creates an array of property values. The first index of this array corresponds to the first property value, which you can retrieve.

Remember, while the order of properties in an object might be consistent in most browsers, it's not guaranteed by the ECMAScript specification. Therefore, using these methods might not always provide reliable results across all implementations.

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