blocks|key|180602|text|"use+strict";|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|entityRanges|data|180603|基本上它启用了严格模式。|180604|180605|严格模式是一种允许您将程序或函数置于“严格”操作上下文中的功能。在严格的操作上下文中，方法表单像以前一样将其绑定到对象。函数形式将其绑定到未定义的对象，而不是全局集合对象。|blockquote|180606|180607|180608|根据您的评论，您将会有一些不同之处。但这是你的假设。Node.js代码只是您的JavaScript代码。所有Node.js代码都由+JavaScript+engine解释。V8+JavaScript+Engine是谷歌为Chrome+web浏览器开发的开源JavaScript引擎。|BOLD|180609|因此，Chrome浏览器和Node.js对"use+strict";的解释不会有太大区别。|180610|请阅读什么是JavaScript中的严格模式。|180611|有关详细信息，请参阅：|180612|180613|Strict+mode|ordered-list-item|180614|ECMAScript+5+Strict+mode+support+in+browsers|180615|Strict+mode+is+coming+to+town|180616|Compatibility+table+for+strict+mode|180617|Stack+Overflow+questions:+what+does+'use+strict'+do+in+JavaScript+&+what+is+the+reasoning+behind+it|180618|180619|​|180620|180621|ECMAScript+6:|180622|180623|ECMAScript+6代码&严格模式。以下是简要的from+the+specification|180624|180625|+10.2.1严格模式代码|180626|180627|可以使用无限制或严格模式语法和语义来处理ECMAScript脚本语法单元。在以下情况下，代码被解释为严格模式代码：|180628|180629|如果以包含使用严格指令的指令开头(参见14.1.1).|180630|Module代码总是严格模式code.|unordered-list-item|180631|
|180632|All部分ClassDeclaration或ClassExpression是严格模式代码)，则|180633|180634|全局代码是严格模式代码。如果以包含使用严格指令的指令开头，或者如果对eval的调用是包含在严格模式code.|180635|180636|Function代码中的直接eval+(参见12.3.4.1)，则|180637|180638|评估代码是严格模式代码。FunctionExpression、GeneratorDeclaration、GeneratorExpression、MethodDefinition或ArrowFunction包含在严格模式代码中，或者如果生成函数[ECMAScriptCode]内部插槽的值的代码以包含Use+strict+Directive.|180639|180640|Function代码(作为参数提供给内置函数)的指令开头，则生成器构造函数是严格模式代码(如果最后一个参数是字符串，则在处理时该字符串是以包含Use+Strict指令的指令开头的FunctionBody。|180641|180642|此外，如果您不知道当前版本的Node.js支持哪些功能，此node.green可以帮助您(利用与kangax相同的数据)。|180643|entityMap|0|LINK|mutability|MUTABLE|url|http://en.wikipedia.org/wiki/V8_%2528JavaScript_engine%2529|1|https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions_and_function_scope/Strict_mode|2|http://www.novogeek.com/post/ECMAScript-5-Strict-mode-support-in-browsers-What-does-this-mean.aspx|3|http://www.yuiblog.com/blog/2010/12/14/strict-mode-is-coming-to-town/|4|https://kangax.github.io/compat-table/strict-mode/|5|https://stackoverflow.com/questions/1335851/what-does-use-strict-do-in-javascript-and-what-is-the-reasoning-behind-it|6|http://www.ecma-international.org/ecma-262/6.0/#sec-strict-mode-code|7|http://node.green/|8|https://kangax.github.io/compat-table/es6/^0|0|D|0|0|0|0|0|0|2E|K|1T|I|0|0|L|D|0|0|0|0|0|B|1|0|0|18|2|0|0|T|3|0|0|Z|4|0|0|2R|5|0|0|0|0|0|D|0|0|Q|M|6|0|0|1|C|0|0|0|0|0|0|J|0|0|0|0|0|0|0|0|0|0|0|0|T|A|7|1C|6|8|0^^$0|@$1|2|3|4|5|6|7|30|8|@$9|31|A|32|B|C]]|D|@]|E|$]]|$1|F|3|G|5|6|7|33|8|@]|D|@]|E|$]]|$1|H|3|-4|5|6|7|34|8|@]|D|@]|E|$]]|$1|I|3|J|5|K|7|35|8|@]|D|@]|E|$]]|$1|L|3|-4|5|6|7|36|8|@]|D|@]|E|$]]|$1|M|3|-4|5|6|7|37|8|@]|D|@]|E|$]]|$1|N|3|O|5|6|7|38|8|@$9|39|A|3A|B|P]]|D|@$9|3B|A|3C|1|3D]]|E|$]]|$1|Q|3|R|5|6|7|3E|8|@$9|3F|A|3G|B|C]]|D|@]|E|$]]|$1|S|3|T|5|6|7|3H|8|@]|D|@]|E|$]]|$1|U|3|V|5|6|7|3I|8|@]|D|@]|E|$]]|$1|W|3|-4|5|6|7|3J|8|@]|D|@]|E|$]]|$1|X|3|Y|5|Z|7|3K|8|@]|D|@$9|3L|A|3M|1|3N]]|E|$]]|$1|10|3|11|5|Z|7|3O|8|@]|D|@$9|3P|A|3Q|1|3R]]|E|$]]|$1|12|3|13|5|Z|7|3S|8|@]|D|@$9|3T|A|3U|1|3V]]|E|$]]|$1|14|3|15|5|Z|7|3W|8|@]|D|@$9|3X|A|3Y|1|3Z]]|E|$]]|$1|16|3|17|5|Z|7|40|8|@]|D|@$9|41|A|42|1|43]]|E|$]]|$1|18|3|-4|5|6|7|44|8|@]|D|@]|E|$]]|$1|19|3|1A|5|6|7|45|8|@]|D|@]|E|$]]|$1|1B|3|-4|5|6|7|46|8|@]|D|@]|E|$]]|$1|1C|3|1D|5|6|7|47|8|@$9|48|A|49|B|P]]|D|@]|E|$]]|$1|1E|3|1A|5|6|7|4A|8|@]|D|@]|E|$]]|$1|1F|3|1G|5|6|7|4B|8|@]|D|@$9|4C|A|4D|1|4E]]|E|$]]|$1|1H|3|-4|5|6|7|4F|8|@]|D|@]|E|$]]|$1|1I|3|1J|5|K|7|4G|8|@$9|4H|A|4I|B|P]]|D|@]|E|$]]|$1|1K|3|-4|5|6|7|4J|8|@]|D|@]|E|$]]|$1|1L|3|1M|5|6|7|4K|8|@]|D|@]|E|$]]|$1|1N|3|-4|5|6|7|4L|8|@]|D|@]|E|$]]|$1|1O|3|1P|5|6|7|4M|8|@]|D|@]|E|$]]|$1|1Q|3|1R|5|1S|7|4N|8|@$9|4O|A|4P|B|P]]|D|@]|E|$]]|$1|1T|3|1U|5|6|7|4Q|8|@]|D|@]|E|$]]|$1|1V|3|1W|5|1S|7|4R|8|@]|D|@]|E|$]]|$1|1X|3|1U|5|6|7|4S|8|@]|D|@]|E|$]]|$1|1Y|3|1Z|5|1S|7|4T|8|@]|D|@]|E|$]]|$1|20|3|1U|5|6|7|4U|8|@]|D|@]|E|$]]|$1|21|3|22|5|1S|7|4V|8|@]|D|@]|E|$]]|$1|23|3|1U|5|6|7|4W|8|@]|D|@]|E|$]]|$1|24|3|25|5|1S|7|4X|8|@]|D|@]|E|$]]|$1|26|3|1U|5|6|7|4Y|8|@]|D|@]|E|$]]|$1|27|3|28|5|1S|7|4Z|8|@]|D|@]|E|$]]|$1|29|3|-4|5|6|7|50|8|@]|D|@]|E|$]]|$1|2A|3|2B|5|6|7|51|8|@]|D|@$9|52|A|53|1|54]|$9|55|A|56|1|57]]|E|$]]|$1|2C|3|-4|5|6|7|58|8|@]|D|@]|E|$]]]|2D|$2E|$5|2F|2G|2H|E|$2I|2J]]|2K|$5|2F|2G|2H|E|$2I|2L]]|2M|$5|2F|2G|2H|E|$2I|2N]]|2O|$5|2F|2G|2H|E|$2I|2P]]|2Q|$5|2F|2G|2H|E|$2I|2R]]|2S|$5|2F|2G|2H|E|$2I|2T]]|2U|$5|2F|2G|2H|E|$2I|2V]]|2W|$5|2F|2G|2H|E|$2I|2X]]|2Y|$5|2F|2G|2H|E|$2I|2Z]]]]

<code>"use strict";</code>

Basically it enables the strict mode.

<blockquote>
 Strict Mode is a feature that allows you to place a program, or a function, in a "strict" operating context. In strict operating context, the method form binds this to the objects as before. The function form binds this to undefined, not the global set objects.
</blockquote>

As per your comments you are telling some differences will be there. But it's your assumption. The Node.js code is nothing but your JavaScript code. All Node.js code are interpreted by the <a href="http://en.wikipedia.org/wiki/V8_%28JavaScript_engine%29" rel="noreferrer">V8 JavaScript engine</a>. The V8 JavaScript Engine is an open source JavaScript engine developed by Google for Chrome web browser.

So, there will be no major difference how <code>"use strict";</code> is interpreted by the Chrome browser and Node.js.

Please read what is strict mode in JavaScript.

For more information:

<ol>
<li><a href="https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Functions_and_function_scope/Strict_mode" rel="noreferrer">Strict mode</a></li>
<li><a href="http://www.novogeek.com/post/ECMAScript-5-Strict-mode-support-in-browsers-What-does-this-mean.aspx" rel="noreferrer">ECMAScript 5 Strict mode support in browsers</a></li>
<li><a href="http://www.yuiblog.com/blog/2010/12/14/strict-mode-is-coming-to-town/" rel="noreferrer">Strict mode is coming to town</a></li>
<li><a href="https://kangax.github.io/compat-table/strict-mode/" rel="noreferrer">Compatibility table for strict mode</a></li>
<li><a href="https://stackoverflow.com/questions/1335851/what-does-use-strict-do-in-javascript-and-what-is-the-reasoning-behind-it">Stack Overflow questions: what does 'use strict' do in JavaScript &amp; what is the reasoning behind it</a></li>
</ol>

<hr/>
ECMAScript 6:

ECMAScript 6 Code &amp; strict mode. Following is brief <a href="http://www.ecma-international.org/ecma-262/6.0/#sec-strict-mode-code" rel="noreferrer">from the specification</a>:

<blockquote>
 10.2.1 Strict Mode Code
 
 An ECMAScript Script syntactic unit may be processed using either unrestricted or strict mode syntax and semantics. Code is interpreted as strict mode code in the following situations:
 
 <ul>
 <li>Global code is strict mode code if it begins with a Directive Prologue that contains a Use Strict Directive (see 14.1.1).</li>
 <li>Module code is always strict mode code.</li>
 <li>All parts of a ClassDeclaration or a ClassExpression are strict mode code.</li>
 <li>Eval code is strict mode code if it begins with a Directive Prologue that contains a Use Strict Directive or if the call to eval is a direct eval (see 12.3.4.1) that is contained in strict mode code.</li>
 <li>Function code is strict mode code if the associated FunctionDeclaration, FunctionExpression, GeneratorDeclaration, GeneratorExpression, MethodDefinition, or ArrowFunction is contained in strict mode code or if the code that produces the value of the function’s [[ECMAScriptCode]] internal slot begins with a Directive Prologue that contains a Use Strict Directive.</li>
 <li>Function code that is supplied as the arguments to the built-in Function and Generator constructors is strict mode code if the last argument is a String that when processed is a FunctionBody that begins with a Directive Prologue that contains a Use Strict Directive.</li>
 </ul>
</blockquote>

Additionally if you are lost on what features are supported by your current version of Node.js, this <a href="http://node.green/" rel="noreferrer">node.green</a> can help you (leverages from the same data as <a href="https://kangax.github.io/compat-table/es6/" rel="noreferrer">kangax</a>).

I have started to explore the Node.js and wrote many demo web application, to understand the flow of Node.js, Express.js, jade, etc.. 

But one thing I came across recently, is the statement <code>"use strict"</code> as the first line inside every function and every <code>.js</code> file.

How exactly is it is interpreted by Node.js?

How is the 'use strict' statement interpreted in Node.js?

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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我已经开始探索Node.js，并写了很多演示web应用程序，以了解Node.js、Express.js、jade等的流程。但我最近遇到的一件事是，将"use strict"语句作为每个函数和每个.js文件中的第一行。Node.js到底是如何解释它的？

在Node.js中“use strict”语句是如何解释的？-腾讯云开发者社区-腾讯云

问在Node.js中“use strict”语句是如何解释的？
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