blocks|key|348237|text|我觉得这不重要。如果它让你感觉更好，你可以做一个空存根函数。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|348238|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I don't think it matters. If it makes you feel better, you can make an empty stub function.

blocks|key|348268|text|我不认为在我看来这是一个教条主义的答案。你在做什么is...creative。如果你对此不满意，那可能是考虑其他选择的一个迹象。但是，如果你对那些不太舒服，那么这可能是一个迹象，这是一个正确的事情(也许是最小的错误)做。最终，你可以通过在这一行之外发表评论来减轻混乱。我不会让你自己的宗教信仰超过最佳实践。只要愿意坚持你的选择。不管怎样，你已经向我证明了这一点。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|348269|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I don't think there's a dogmatic answer to this in my opinion. What you're doing is...creative. If you're not comfortable with it, that could be a sign to consider other options. But if you're even less comfortable with those then that could be a sign this is the right thing (or maybe the least wrong thing) to do. Ultimately you could mitigate the confusion by commenting the heck out of that line. I wouldn't let yourself get religious over best practices. Just be willing to stand by your choice. You've justified it to me, anyway.

blocks|key|381041|text|问得好。它不应该引起任何JavaScript问题。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|381042|其他需要考虑的事情:当你这样做的时候，你可能会把你的管理能力暴露给世界，这对黑客来说可能是有用的。这可能不是什么大问题，但这是值得注意的。|381043|另请参阅：|381044|381045|+Why+can+I+use+a+function+before+it’s+defined+in+Javascript?|blockquote|offset|length|381046|381047|entityMap|0|LINK|mutability|MUTABLE|url|https://stackoverflow.com/questions/261599/why-can-i-use-a-function-before-its-defined-in-javascript^0|0|0|0|0|1|1N|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|W|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|X|8|@]|9|@]|A|$]]|$1|G|3|H|5|I|7|Y|8|@]|9|@$J|Z|K|10|1|11]]|A|$]]|$1|L|3|-4|5|6|7|12|8|@]|9|@]|A|$]]|$1|M|3|-4|5|6|7|13|8|@]|9|@]|A|$]]]|N|$O|$5|P|Q|R|A|$S|T]]]]

Good question. It shouldn't cause any JavaScript problems.
Other things to consider: you are potentially exposing your admin capabilities to the world when you do this, which might be useful to hackers. That's probably not much of a concern, but it is something to be aware of.
<h3>See also:</h3>
<blockquote>
<a href="https://stackoverflow.com/questions/261599/why-can-i-use-a-function-before-its-defined-in-javascript">Why can I use a function before it’s defined in Javascript?</a>
</blockquote>

blocks|key|150717|text|代码的操作应该没有错误，因为没有实现的管理函数将不会被调用。唯一真正浪费的是传输未使用的管理代码的带宽。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|150718|然而，请允许我以默默无闻的方式告诫安全。如果用户要查看这段代码，并看到有他们无法访问的管理函数，他们可能会感到好奇，并尝试下载"admin.js“文件并查看这些函数的功能。如果您唯一的阻止管理功能被执行的块是停止包含文件，那么一些狡猾的用户可能会很快找到一种方法来调用管理函数，而他们不应该能够这样做。|150719|如果您已经为管理函数进行了服务器端身份验证/权限检查，只需忽略我的上一段:-)|150720|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|H|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|I|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|J|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|G|$]]

The code should operate without error, since the admin functions without implementation will not be called. The only thing that is really being wasted is bandwidth to transmit the admin code that is not used.

However, let me caution against security through obscurity. If the user were to view this code and see that there are admin functions that they cannot access, they might get curious and try to download the "admin.js" file and see what these functions do. If your only block to keeping admin functions from being performed is to stop including the file, then some crafty user will probably quickly find a way to call the admin functions when they should not be able to. 

If you already do server side authentication/permissions checking for the admin function calls just ignore my previous paragraph :-)

blocks|key|149085|text|就我个人而言，我会在admin.js中绑定(或重新绑定)事件：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|149086|$(function()+{

$(".something").dblclick(function(){
++adminstuff();
});

});

function+adminstuff()
{
++//+...
}|code-block|syntax|javascript|149087|通过这种方式，adminstuff()调用和函数对“普通”用户是不可见的。|149088|entityMap^0|0|0|0^^$0|@$1|2|3|4|5|6|7|K|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|L|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|M|8|@]|9|@]|A|$]]|$1|I|3|-4|5|6|7|N|8|@]|9|@]|A|$]]]|J|$]]

Personally, I would bind (or re-bind) the event in admin.js:

<pre><code>$(function() {

$(".something").dblclick(function(){
 adminstuff();
});

});

function adminstuff()
{
 // ...
}
</code></pre>

That way, the adminstuff() call and the function will not be visible to "normal" users.

blocks|key|150732|text|Javascript是动态的-它不应该关心函数是否被定义。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|150733|如果您将管理函数放在命名空间对象中(可能是一个很好的实践)，那么您有几个选项。|150734|150735|检查管理对象中的函数是否存在|ordered-list-item|150736|检查是否存在管理对象(可能替换您的标志)|150737|有一个操作对象，其中管理文件在加载时替换select函数。(更好的做法是，使用原型继承来隐藏它们。)|150738|。|150739|entityMap^0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|P|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|Q|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|R|8|@]|9|@]|A|$]]|$1|E|3|F|5|G|7|S|8|@]|9|@]|A|$]]|$1|H|3|I|5|G|7|T|8|@]|9|@]|A|$]]|$1|J|3|K|5|G|7|U|8|@]|9|@]|A|$]]|$1|L|3|M|5|6|7|V|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|O|$]]

Javascript is dynamic - it shouldn't care if the functions aren't defined.

If you put your admin functions in a namespace object (probably a good practice anyway), you have a couple of options.

<ol>
<li>Check for the existence of the function in the admin object</li>
<li>Check for the existence of the admin object (possibly replacing your flag)</li>
<li>Have an operations object instead, where the admin file replaces select functions when it loads. (Even better, use prototypical inheritance to hide them.)</li>
</ol>

blocks|key|381181|text|我认为你应该小心，因为你在为大规模的安全问题做准备。在firebug中，将一个变量(如admin+)更改为"true“非常简单，而且由于admin.js是公开访问的，因此仅在页面中不包含它是不够的，因为将另一个脚本标记添加到带有firebug的页面也很简单。在这种情况下，知识渊博的用户可以轻松地给自己授予管理权限。我不认为您应该依赖纯粹的客户端安全模型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|381182|entityMap^0|0^^$0|@$1|2|3|4|5|6|7|D|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|E|8|@]|9|@]|A|$]]]|C|$]]

I think you should be wary that you are setting yourself up for massive security issues. It is pretty trivial in firebug to change a variable such as admin to "true", and seeing as admin.js is publically accessible, its not enough to simple not include it on the page, as it is also simple to add another script tag to the page with firebug. A moderately knowledgeable user could easily give themselves admin rights in this scenario. I don't think you should ever rely on a purely client side security model.

The problem: I have a jQuery heavy page that has a built in admin interface. The admin functions only trigger when an admin variable is set. These functions require a second library to work properly and the second file is only included if the user is an admin when the page is first created. The functions will never trigger for normal users and normal users do not get the include for the second library.

Is it bad to reference a function does not exist in the files currently included even if that function can never be called? (does that make sense :)

Pseudocode:

header: (notice that admin.js is not included)

<pre><code>&lt;script type="text/javascript" src="script.js"&gt;&lt;/script&gt;
&lt;script type="text/javascript" src="user.js"&gt;&lt;/script&gt;
</code></pre>

script.js: (admin functions referenced but can't be executed)

<pre><code>admin = false; // Assume this

$(".something").dblclick(function(){
 if(admin)
 adminstuff(); // Implemented in admin.js (not included)
 else
 userstuff();
});
</code></pre>

Ideas:
I suppose two separate files for users and admins could be used but I feel that would be an overly complicated solution (don't want to maintain two large files with only a few lines of difference). The only reason I include a reference to the admin function in this file is I need to attach it to page elements that get refreshed as a part of the script. When jQuery refreshes the page I need to reattach function to interactive elements.

The Question:
I want to keep things very simple and not have to include file I don't have to if they will not be used by the user. Is this a good way to do this or should I be going another route?

A question about referencing functions in Javascript

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

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问题：，我有一个内置管理界面的jQuery页面。管理函数只在设置管理变量时触发。这些函数需要第二个库才能正常工作，只有在第一次创建页面时用户是管理员时才会包含第二个文件。函数永远不会为普通用户触发，而普通用户不会获得第二个库的包含。引用当前包含的文件中不存在的函数是否不好，即使该函数永远不会被调用？(这有道理吗？)伪码...

问关于Javascript中引用函数的一个问题
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