有两种方法可以动态合并javascript对象的属性。他们是
Object.assign()方法被用于从一个或多个源对象的所有属性的值复制到目标对象。它将返回目标对象。
<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>{"a":"ram","b":"rahim","c":"akbar","d":"anthony"}
{"a":"ram","b":"rahim","c":"akbar","d":"anthony"}如果对象具有相同的键，则将复制分发中稍后出现的对象的键值。下面的示例显示了当存在具有不同值的相同键时的情况。
<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>{"a":"ram","b":"akbar","d":"anthony"}
{"a":"ram","b":"akbar","d":"anthony"}该价差运算符允许表达在多个元素/变量/参数预期的地方进行扩展。它主要用于需要多个值的变量数组中。由于javascript对象是键值配对的实体，因此我们可以使用传播运算符将它们合并为一个。
var target = [...obj1, ...obj2, ...]
<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>{"a":"ram","b":"akbar","d":"anthony"}