无法读取 null 的属性“样式” - 在 Chrome 的 Javascript 控制台中
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Cannot read property 'style' of null - in Chrome's Javascript Console
提问by Livingston
I was checking the JS console out and it helped me fix a few minor issues, but I would like to know if this warning is anything to seriously worry about?
我正在检查 JS 控制台，它帮助我解决了一些小问题，但我想知道这个警告是否值得认真担心？
This is the code which gives the error:
这是给出错误的代码：
<script type="text/javascript"
src="https://www.safaviehhome.com/product_images/locations/js/jqgalscroll.js"></script>
<script src="https://www.safaviehhome.com/product_images/mainnav/stuHover.js" type="text/javascript"></script>
<script>
function layerSetup(id,visibility){
if(document.getElementById){
this.obj = document.getElementById(id).style;
Uncaught TypeError: Cannot read property 'style' of null
Uncaught TypeError: Cannot read property 'style' of null
<!--Includes many more of the same "Cannot read property 'style' of null messages -->
this.obj.visibility = visibility;
return this.obj;}
else if(document.all){
this.obj = document.all[id].style;
this.obj.visibility = visibility;
return this.obj;}
else if(document.layers){
this.obj = document.layers[id];
this.obj.visibility = visibility;
return this.obj;}
}
function visVisible(param){
new layerSetup(param,'visible');
}
function visHidden(param){
new layerSetup(param,'hidden');
}</script>
I cannot really figure out why this is happening and whether it's something I should worry about since our Rug categories function fine. Can anybody offer any insight? I apologize for not offering any of my own explanations but I didn't write this JS a former co-worked did and it's now up to me to debug every mistake he made. It's a learning process but I'm still somewhat new to this ..
我真的无法弄清楚为什么会发生这种情况以及是否应该担心，因为我们的地毯类别功能正常。任何人都可以提供任何见解吗？我很抱歉没有提供我自己的任何解释，但我并没有像以前的同事那样写这个 JS，现在由我来调试他犯的每个错误。这是一个学习过程，但我对此还是有些陌生..
回答by Jivings
This could be happening for two reasons.
这可能有两个原因。
- Somewhere on the page the
layerSetupfunction is being called withnullas one of the parameters. - An element with the id being passed the the
layerSetupfunction does not exist on the page.
- 在页面上的某个地方，
layerSetup函数被null作为参数之一调用。 - 传递 id 的元素
layerSetup在页面上不存在该函数。
In the Chrome dev console you can click Pause on All Exceptions, a button in the bottom left bar with a pausesymbol. This will help you to determine what the parameters are that are being passed to the function.
在 Chrome 开发者控制台中，您可以单击Pause on All Exceptions左下栏中带有暂停符号的按钮。这将帮助您确定传递给函数的参数是什么。
