语法错误: 私有字段不能被删除

当对类的私有属性或对象的私有属性使用 delete 时，会发生 JavaScript 异常 "SyntaxError: private fields can't be deleted"。 私有属性。

消息

SyntaxError: Private fields can not be deleted (V8-based)
SyntaxError: private fields can't be deleted (Firefox)
SyntaxError: Cannot delete private field X (Safari)

错误类型

SyntaxError

哪里出了问题？

代码尝试对对象或类的私有属性（字段或方法）进行 delete 操作。这是 JavaScript 禁止的——私有属性不能动态添加或删除。

示例

js
class MyClass {
  #myPrivateField;
  deleteIt() {
    delete this.#myPrivateField; // SyntaxError: private fields can't be deleted
  }
}
js
class MyClass {
  #myPrivateMethod() {
  }
  #deleteIt() {
    delete this.#myPrivateMethod; // SyntaxError: private fields can't be deleted
  }
}

另请参阅