blocks|key|2017811|text|当你打算缩减你的代码时，这也很重要。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2017812|因此，我个人会在每个}之后添加一个，而ASI(+automatic+semicolon+insertion+)会在其中插入一个。|offset|length|style|CODE|2017813|我写了一篇关于ASI+in+JavaScript的文章。|2017814|entityMap|0|LINK|mutability|MUTABLE|url|https://en.wikipedia.org/wiki/JavaScript_syntax#Whitespace_and_semicolons|1|http://blog.alexanderdickson.com/javascript-semicolons^0|0|A|1|O|T|0|0|7|H|1|0^^$0|@$1|2|3|4|5|6|7|T|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|U|8|@$D|V|E|W|F|G]]|9|@$D|X|E|Y|1|Z]]|A|$]]|$1|H|3|I|5|6|7|10|8|@]|9|@$D|11|E|12|1|13]]|A|$]]|$1|J|3|-4|5|6|7|14|8|@]|9|@]|A|$]]]|K|$L|$5|M|N|O|A|$P|Q]]|R|$5|M|N|O|A|$P|S]]]]

It matters too when you intend to minify your code.
So I personally add one after every <code>}</code> where <a href="https://en.wikipedia.org/wiki/JavaScript_syntax#Whitespace_and_semicolons" rel="nofollow noreferrer">automatic semicolon insertion</a> (ASI) would insert one.
I wrote a post about <a href="http://blog.alexanderdickson.com/javascript-semicolons" rel="nofollow noreferrer">ASI in JavaScript</a>.

blocks|key|2018209|text|您永远不需要这样做；您总是可以这样做(除了在else和while之前)。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|2018210|解释：|2018211|不幸的是，JavaScript分号是可选的。|2018212|因此，您永远不需要添加分号。|2018213|以分号结束每条语句是(非常)好的做法。|2018214|唯一以}结尾的语句是以对象文字(例如JSON)或函数表达式结尾的语句。|2018215|因此，最佳做法是将分号放在以下两个大括号后面(仅限)：|2018216|var+myFunc+=+function()+{+};
var+myobject+=+{+};|code-block|syntax|javascript|2018217|entityMap^0|M|4|R|5|0|0|0|0|0|3|1|0|0|0^^$0|@$1|2|3|4|5|6|7|Y|8|@$9|Z|A|10|B|C]|$9|11|A|12|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|13|8|@]|D|@]|E|$]]|$1|H|3|I|5|6|7|14|8|@]|D|@]|E|$]]|$1|J|3|K|5|6|7|15|8|@]|D|@]|E|$]]|$1|L|3|M|5|6|7|16|8|@]|D|@]|E|$]]|$1|N|3|O|5|6|7|17|8|@$9|18|A|19|B|C]]|D|@]|E|$]]|$1|P|3|Q|5|6|7|1A|8|@]|D|@]|E|$]]|$1|R|3|S|5|T|7|1B|8|@]|D|@]|E|$U|V]]|$1|W|3|-4|5|6|7|1C|8|@]|D|@]|E|$]]]|X|$]]

You never need to; you always can (except before <code>else</code> and <code>while</code>).
<h2>Explanation:</h2>
Unfortunately, JavaScript semicolons are optional. 
Therefore, you never need to add a semicolon.
It is (very) good practice to terminate every statement with a semicolon. 
The only statements that end with a <code>}</code> are statements ending with an object literal (e.g. JSON) or function expression.
Therefore, best practice is to put semicolons after the following two braces (only):
<pre><code>var myFunc = function() { };
var myobject = { };
</code></pre>

blocks|key|2018269|text|分号位于不以大括号结尾的行的末尾，也不是用来分隔同一行上的语句。在使用闭合支架后使用它们没有坏处，或者穿吊带和腰带，但它看起来确实有点书呆子。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2018270|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|$]]

Semicolons go at the end of lines that do not end in a curly brace or to separate statements on the same line. It does no harm to use them after a closing brace, or to wear suspenders and a belt, but it does look a little nerdy.

blocks|key|1804673|text|不要使用分号：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|1804674|...if这只是你每天的函数声明：|1804675|function+foo()+{

}+//+No+semicolon|code-block|syntax|javascript|1804676|使用分号：|1804677|...if这是一个任务：|1804678|var+foo+=+function()+{

};+//+Semicolon|1804679|...or自调用函数：|1804680|(function+()+{

})();+//+Semicolon|1804681|entityMap^0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|U|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|V|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|W|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|X|8|@]|9|@]|A|$]]|$1|K|3|L|5|6|7|Y|8|@]|9|@]|A|$]]|$1|M|3|N|5|F|7|Z|8|@]|9|@]|A|$G|H]]|$1|O|3|P|5|6|7|10|8|@]|9|@]|A|$]]|$1|Q|3|R|5|F|7|11|8|@]|9|@]|A|$G|H]]|$1|S|3|-4|5|6|7|12|8|@]|9|@]|A|$]]]|T|$]]

<h2>Don't use a semicolon:</h2>

...if it's just your every-day function declaration:

<pre><code>function foo() {

} // No semicolon
</code></pre>

 

<h2>Use a semicolon:</h2>

...if it's an assignment:

<pre><code>var foo = function() {

}; // Semicolon
</code></pre>

 
...or a self invoking function:

<pre><code>(function () {

})(); // Semicolon
</code></pre>

blocks|key|2018370|text|考虑下面的代码：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2018371|//+This+will+break+code

a=b=c=d=e=1
a+=+b+%2B+c+++++//+Semicolon+required+here
(d+%2B+e).toString()|code-block|syntax|javascript|2018372|它将返回"Property+of+object+object+is+not+a+function“。因为它实际上将被执行为：|2018373|a+=+b+%2B+c(d+%2B+e).toString()|2018374|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|N|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|O|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|P|8|@]|9|@]|A|$E|F]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

Consider this code:
<pre><code>// This will break code

a=b=c=d=e=1
a = b + c // Semicolon required here
(d + e).toString()
</code></pre>
It will return &quot;Property of object [object Object] is not a function&quot;. Because it will actually be executed as:
<pre><code>a = b + c(d + e).toString()
</code></pre>

blocks|key|2018399|text|在JavaScript中的函数中返回函数后，还应该在花括号后面使用分号。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2018400|function+watchOut(problem)+{
++return+function(number,+location)+{
++++alert("Be+careful!+There+are+"+%2B+problem+%2B
++++++++++"+today!\n"+%2B

++++++++++number+%2B+"+have+been+spotted+at+the+"+%2B+location+%2B+"!"
++++);
++};
}|code-block|syntax|javascript|2018401|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|I|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|J|8|@]|9|@]|A|$E|F]]|$1|G|3|-4|5|6|7|K|8|@]|9|@]|A|$]]]|H|$]]

You also should use a semicolon after a curly bracket after returning a function within a function in JavaScript.
<pre><code>function watchOut(problem) {
 return function(number, location) {
 alert(&quot;Be careful! There are &quot; + problem +
 &quot; today!\n&quot; +

 number + &quot; have been spotted at the &quot; + location + &quot;!&quot;
 );
 };
}
</code></pre>

Many times I've seen a semicolon used after a function declaration, or after the anonymous "return" function of a Module Pattern script. When is it appropriate to use a semicolon after curly braces?

When should I use a semicolon after curly braces?

JSON

我曾多次看到在函数声明之后或模块模式脚本的匿名“返回”函数之后使用分号。什么时候在大括号后使用分号是合适的？

问什么时候我应该在大括号后使用分号？
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问什么时候我应该在大括号后使用分号？
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