javascript “未捕获的类型错误：无法读取属性”JS 错误是什么意思？
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What does the "Uncaught TypeError: Cannot read property" JS error mean?
提问by Jobvdweerd
Can someone explain to me what these errors mean?
有人可以向我解释这些错误是什么意思吗？
I need the answers for a school project.
我需要学校项目的答案。
Error 1 "Uncaught TypeError: Cannot read property 'getBoundingClientRect' of null"
Error 2 "Uncaught TypeError: Cannot read property 'dom' of null"
回答by JimmyRare
It means you are trying to use a property on something that is null. Make sure you have an object to operate on before trying to use the property. I.e getBoundingClientRectexpects a dom element.
这意味着您正在尝试对null 的内容使用属性。在尝试使用该属性之前，请确保您有一个要操作的对象。即getBoundingClientRect期望一个 dom 元素。
One way to select a dom element is by id:
选择 dom 元素的一种方法是通过 id：
var element = document.getElementById('myElement');
var element = document.getElementById('myElement');
