javascript JS 错误信息 textContent 设置为 null
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JS error message textContent set as null
提问by Cam C
I am fairly new to JS and the world of web development, so apologise in advance if my question is a bit tedious.
我对 JS 和 Web 开发世界还很陌生，所以如果我的问题有点乏味，请提前道歉。
I wrote this code:
我写了这段代码：
var breakfast = new Object();
breakfast.food = "croissant";
breakfast.extra = ["mushroom", "cheese"];
breakfast.eat = function(){return this.food + " with " + this.extra[0];}
var elBreakfast = document.getElementById("breakf");
elBreakfast.textContent = breakfast.eat();
I get an error message from the browser:
我从浏览器收到一条错误消息：
"Uncaught TypeError: Cannot set property 'textContent' of null"...
What have I done wrong?
我做错了什么？
Thanks!
谢谢！
回答by jAndy
The only important code here is document.getElementById("breakf");. It seems like your browser is unable to query for the element with an ID of breakfwithin your HTML markup.
这里唯一重要的代码是document.getElementById("breakf");. 您的浏览器似乎无法breakf在您的 HTML 标记中查询 ID 为 的元素。
So you need to check your HTML code live in your browser. Check if there is any HTML node with id=breakf. If not, you correctly should receive that error.
因此，您需要在浏览器中实时检查 HTML 代码。检查是否有任何带有id=breakf. 如果没有，您应该正确地收到该错误。
回答by Bhanuprathap Bussa
Try to add script reference end of body tag in html page so that it will load breakf element and then applies the breakfast.eat();
尝试在 html 页面中添加 body 标签的脚本引用结束，以便它加载 breakf 元素，然后应用早餐.eat();
回答by Lilian Tedone
The error is coming from document.getElementById("breakf")here.
The browser can't seem to find a node with an id of breakf.
错误来自document.getElementById("breakf")这里。浏览器似乎无法找到 ID 为 的节点breakf。
Check your html code for a node with id="breakf", if it's not there, add it to the node you want to write text in and it should be good.
检查带有 的节点的 html 代码id="breakf"，如果它不存在，请将其添加到要写入文本的节点，它应该很好。
