如何动态合并两个 JavaScript 对象的属性?
javascriptobject oriented programmingprogramming
有两种方法可以动态合并 JavaScript 对象的属性。它们是
1) Object.assign()
Object.assign() 方法用于将所有属性的值从一个或多个源对象复制到目标对象。它将返回目标对象。
示例 1
<html>
<body>
<script>
var target = { a: "ram", b: "rahim" };
var source = { c: "akbar", d: "anthony" };
var returnedTarget = Object.assign(target, source);
document.write(JSON.stringify(target));
document.write(JSON.stringify(returnedTarget));
</script>
</body>
</html>
输出
{"a":"ram","b":"rahim","c":"akbar","d":"anthony"}
{"a":"ram","b":"rahim","c":"akbar","d":"anthony"}
如果对象有相同的键，则复制分发中较后出现的对象的键的值。以下示例显示了有相同键但值不同的情况。
示例 2
<html>
<body>
<script>
var target = { a: "ram", b: "rahim" };
var source = { b: "akbar", d: "anthony" };
var returnedTarget = Object.assign(target, source);
document.write(JSON.stringify(target));
document.write("</br>");
document.write(JSON.stringify(returnedTarget));
</script>
</body>
</html>
输出
{"a":"ram","b":"akbar","d":"anthony"}
{"a":"ram","b":"akbar","d":"anthony"}
2) 使用扩展运算符
扩展运算符允许在需要多个元素/变量/参数的地方扩展表达式。它主要用于需要多个值的变量数组中。由于 javascript 对象是键值对实体，我们可以使用扩展运算符将它们合并为一个。
语法
var target = [...obj1, ...obj2, ...]
示例
<html>
<body>
<script>
var target = { a: "ram", b: "rahim" };
var source = { b: "akbar", d: "anthony" };
var returnedTarget = {...target, ...source}
document.write(JSON.stringify(returnedTarget));
</script>
</body>
</html>
输出
{"a":"ram","b":"akbar","d":"anthony"}
