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WeakRef.prototype.deref()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨2021年4月⁩.

deref方法返回WeakRef 实例的目标对象,如果目标对象已被垃圾收集,则返回undefined

语法

obj = ref.deref();

返回值

返回 WeakRef 的目标对象,如果该对象已被垃圾收集,则返回undefined

说明

有关一些重要说明,请参阅WeakRef页面上的Notes on WeakRefs

示例

使用 deref

有关完整示例,请参阅WeakRef页面的示例部分。

js
const tick = () => {
  // Get the element from the weak reference, if it still exists
  const element = this.ref.deref();
  if (element) {
    element.textContent = ++this.count;
  } else {
    // The element doesn't exist anymore
    console.log("The element is gone.");
    this.stop();
    this.ref = null;
  }
};

规范

Specification
ECMAScript® 2026 Language Specification
# sec-weak-ref.prototype.deref

浏览器兼容性

参见