TypeError: null/undefined has no properties
当您尝试访问 null 和 undefined 的属性时，会发生 JavaScript 异常 "null（或 undefined）没有属性"。它们没有任何属性。
消息
TypeError: Cannot read properties of undefined (reading 'x') (V8-based) TypeError: Cannot destructure 'x' as it is undefined. (V8-based) TypeError: Cannot destructure property 'x' of 'y' as it is undefined. (V8-based) TypeError: null has no properties (Firefox) TypeError: undefined has no properties (Firefox) TypeError: undefined is not an object (evaluating 'undefined.x') (Safari) TypeError: Right side of assignment cannot be destructured (Safari)
错误类型
哪里出错了？
无论是 null 还是 undefined 都没有您可以访问的属性。因此，您不能在它们上使用属性访问器，也不能对它们进行解构。
示例
null 和 undefined 没有属性
js
null.foo;
// TypeError: null has no properties
undefined.bar;
// TypeError: undefined has no properties