javascript 未捕获的类型错误
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Uncaught TypeError
提问by Daniel Afonso
Can anyone explain what is theses errors?
谁能解释一下这些错误是什么？
Uncaught TypeError: Cannot set property 'innerHTML' of null
Uncaught TypeError: Cannot read property 'style' of null
Uncaught SyntaxError: Unexpected token ILLEGAL
Uncaught TypeError: Object # has no method 'dispatchEvent'
未捕获的类型错误：无法设置 null 的属性“innerHTML”
未捕获的类型错误：无法读取 null 的属性“样式”
未捕获的语法错误：意外的令牌非法
未捕获的类型错误：对象 # 没有方法“dispatchEvent”
This is my test Website
这是我的测试网站
回答by Paolo Stefan
At some point in the page you have:
在页面中的某个点，您有：
function display_price(price, oid)
{
...
element = document.getElementById(oid);
if (valor != 'NaN' && valor != null && valor != '')
{
element.innerHTML = valor + money_simbol;
The last line is causing the error because elementis null. You should add a condition to the if(): that is, change this line:
最后一行导致错误，因为它element为空。您应该在 if(): 中添加一个条件：即更改此行：
if (valor != 'NaN' && valor != null && valor != '')
to this:
对此：
if (element && valor != 'NaN' && valor != null && valor != '')
In other words, it's a good practice to alwayscheck the return value of a function beforeaccessing its properties.
换句话说，在访问其属性之前始终检查函数的返回值是一种很好的做法。
回答by Shadow Wizard is Ear For You
You call the function display_pricepassing it ID of spanthat does not yet exist.
你调用函数display_price传递它的 IDspan还不存在。
Change this line: (appears twice in your code)
更改此行：（在您的代码中出现两次）
display_price('510', 'products_price_id');
To this instead:
改为：
window.onload = function() {
display_price('510', 'products_price_id');
};
This will wait until the page loads before trying to find the element, thus solve your errors.
这将等到页面加载后再尝试查找元素，从而解决您的错误。
