Javascript、getElementById 和样式不起作用：未捕获的类型错误：无法读取 null 的属性“样式”
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Javascript, getElementById and style not working: Uncaught TypeError: Cannot read property 'style' of null
提问by user1269625
I have this code here:
我在这里有这个代码：
document.getElementById('success').style.display("block");
document.getElementById('success').text("aaaa");
and I get this error, why?
我收到这个错误，为什么？
Uncaught TypeError: Cannot read property 'style' of null
<span id="success" style="color:#FFF; display:none;"></span>
I moved my code to bottom of the page and I get this new error now
我将代码移至页面底部，现在出现此新错误
Uncaught TypeError: Property 'display' of object #<CSSStyleDeclaration> is not a function
Uncaught TypeError: Property 'display' of object #<CSSStyleDeclaration> is not a function
采纳答案by Todd
Should be:
应该：
var elSuccess = document.getElementById('success');
elSuccess.style.display = 'block';
elSuccess.innerText = 'aaa';
回答by Hanky Panky
That simply means that at the time of execution of that JavaScript
那只是意味着在执行该 JavaScript 时
document.getElementById('success') // is NULL
Which either means that there is no element with an id successin your document, or it has not loaded so far. Move the Javascript to be called after it has loaded.
这要么意味着success您的文档中没有带有 id 的元素，要么到目前为止还没有加载。在加载后移动要调用的 Javascript。
回答by Aditya Vikas Devarapalli
that means
这意味着
CASE 1:your javascript code is getting executed before the element with that id has loaded on that page or
情况 1：您的 javascript 代码在具有该 id 的元素加载到该页面之前被执行，或者
CASE 2:no element in your document exists with such an id
情况 2：您的文档中不存在具有此类 ID 的元素
if your problem is case 1:
如果您的问题是情况 1：
try to place the javascript code just before the closing </body>tag
尝试将 javascript 代码放在结束</body>标记之前
if it's case 2:
如果是情况 2：
try changing the idof the element in the lines
尝试更改行id中元素的
document.getElementById('success').style.display("block");
document.getElementById('success').text("aaaa");
change the id'success'to some other idthat actually exists
将 更改id'success'为其他id实际存在的
回答by Ricky Wilson
I would suggest using jQuery for this
我建议为此使用 jQuery
$("#success").css("display","block");
$("#success").append("aaa");
回答by PSR
if(document.getElementById('success') != null)
{
................................
}
Element does not exist with id success
元素不存在 id success
