如 ofObjectChanges 建立在 Object.observe() 这是过时的( https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/observe )我正在寻找一种替代方法来观察对象属性的变化。有人知道吗?
最佳答案
也许使用代理是一种选择,尽管需要替换原始对象
const { Subject } = require('rxjs');
// Take an object, and return a proxy with an 'observation$' stream
const toObservableObject = targetObject => {
const observation$ = new Subject();
return new Proxy(targetObject, {
set: (target, name, value) => {
const oldValue = target[name];
const newValue = value;
target[name] = value;
observation$.next({ name, oldValue, newValue });
},
get: (target, name) => name == 'observation$' ? observation$ : target[name]
});
}
const observableObject = toObservableObject({ });
observableObject.observation$
.filter(modification => modification.name == 'something')
.subscribe(({ name, oldValue, newValue }) => console.log(`${name} changed from ${oldValue} to ${newValue}`));
observableObject.something = 1;
observableObject.something = 2;
输出
something changed from undefined to 1
something changed from 1 to 2
在兼容性表中查找 Proxy 当前节点版本已完全支持)
https://kangax.github.io/compat-table/es6/
和代理的文档在
https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Proxy
关于rxjs ofObjectChanges 已过时,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/36001392/