新鲜的空气需要闻 發表於 2019-9-8 22:21:00

JavaScript 注释

<p><span style="font-size: 16px; background-color: rgba(0, 204, 255, 1)"><strong>JavaScript 注释可用于提高代码的可读性。</strong></span></p>
<hr>
<h2><span style="font-size: 18pt; color: rgba(255, 0, 0, 1)"><strong>㈠JavaScript 注释（单行）</strong></span></h2>
<p><span style="font-size: 16px"><strong>JavaScript <span style="background-color: rgba(0, 204, 255, 1)">不会执行注释。</span></strong></span></p>
<p><span style="font-size: 16px"><strong>我们可以添加注释来对 JavaScript 进行解释，或者提高代码的可读性。</strong></span></p>
<p><span style="font-size: 16px"><strong>单行注释以<span style="background-color: rgba(0, 204, 255, 1)">&nbsp;</span><span class="marked"><span style="background-color: rgba(0, 204, 255, 1)">//&nbsp;</span>开头。</span></strong></span></p>
<p>&nbsp;</p>
<p><span style="font-size: 16px"><strong><span class="marked">示例介绍：</span></strong></span></p>
<div class="cnblogs_code">
<pre><span style="font-size: 16px"><strong><span style="color: rgba(0, 0, 255, 1)">&lt;!</span><span style="color: rgba(255, 0, 255, 1)">DOCTYPE html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">meta </span><span style="color: rgba(255, 0, 0, 1)">charset</span><span style="color: rgba(0, 0, 255, 1)">="utf-8"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>单行注释<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">h1 </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myH1"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">h1</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myP"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">//</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)"> 输出标题：</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">document.getElementById(</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">myH1</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">).innerHTML</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">=</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">Welcome to my Homepage</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">;
</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">//</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)"> 输出段落：</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">document.getElementById(</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">myP</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">).innerHTML</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">=</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">This is my first paragraph.</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">;
</span><span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;</span><span style="color: rgba(128, 0, 0, 1)">b</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释：<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">b</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释不会被执行。<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span></strong></span></pre>
</div>
<p>&nbsp;</p>
<p><span style="font-size: 16px; background-color: rgba(0, 204, 255, 1)"><strong>页面输出结果为：</strong></span></p>
<p><span style="font-size: 16px"><strong><img src="https://img2018.cnblogs.com/blog/1746290/201909/1746290-20190908154446505-1873168536.png" alt=""></strong></span></p>
<p>&nbsp;</p>
<p><span style="font-size: 16px"><strong>&nbsp;</strong></span></p>
<p><span style="font-size: 18pt; color: rgba(255, 0, 0, 1)"><strong>㈡JavaScript 多行注释</strong></span></p>
<p><span style="font-size: 16px"><strong>多行注释以&nbsp;<span class="marked"><span style="background-color: rgba(255, 255, 0, 1)">/*</span>&nbsp;开始，以<span style="background-color: rgba(255, 255, 0, 1)">&nbsp;</span><span class="marked"><span style="background-color: rgba(255, 255, 0, 1)">*/&nbsp;</span>结尾。</span></span></strong></span></p>
<p><span style="font-size: 16px"><strong><span class="marked">下面的例子使用多行注释来解释代码：</span></strong></span></p>
<div class="cnblogs_code">
<pre><span style="font-size: 16px"><strong><span style="color: rgba(0, 0, 255, 1)">&lt;!</span><span style="color: rgba(255, 0, 255, 1)">DOCTYPE html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>多行注释<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">meta </span><span style="color: rgba(255, 0, 0, 1)">charset</span><span style="color: rgba(0, 0, 255, 1)">="utf-8"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">h1 </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myH1"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">h1</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myP"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">/*</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">
下面的这些代码会输出
一个标题和一个段落
并将代表主页的开始
</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">*/</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">
document.getElementById(</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">myH1</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">).innerHTML</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">=</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">欢迎来到石海莹的博客</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">;
document.getElementById(</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">myP</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">).innerHTML</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">=</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">这是一个欢迎的段落。</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">;
</span><span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;</span><span style="color: rgba(128, 0, 0, 1)">b</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释：<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">b</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释块不会被执行。<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span></strong></span></pre>
</div>
<p>&nbsp;</p>
<p><span style="font-size: 16px; background-color: rgba(51, 204, 204, 1)"><strong>页面输出结果为：</strong></span></p>
<p><span style="font-size: 16px"><strong><img src="https://img2018.cnblogs.com/blog/1746290/201909/1746290-20190908154801209-983195657.png" alt=""></strong></span></p>
<p>&nbsp;</p>
<p><span style="font-size: 16px"><strong>&nbsp;</strong></span></p>
<h2><span style="font-size: 18pt; color: rgba(255, 0, 0, 1)"><strong>㈢使用注释来阻止执行</strong></span></h2>
<p><span style="font-size: 16px"><strong>⑴<span style="background-color: rgba(51, 204, 204, 1)">示例一</span>：在下面的例子中，注释用于阻止其中一条代码行的执行（可用于调试）：</strong></span></p>
<div class="cnblogs_code">
<pre><span style="font-size: 16px"><strong><span style="color: rgba(0, 0, 255, 1)">&lt;!</span><span style="color: rgba(255, 0, 255, 1)">DOCTYPE html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">meta </span><span style="color: rgba(255, 0, 0, 1)">charset</span><span style="color: rgba(0, 0, 255, 1)">="utf-8"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释组织执行<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">h1 </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myH1"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">h1</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myP"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">//</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">document.getElementById("myH1").innerHTML="这段代码被阻止执行";</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">document.getElementById(</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">myP</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">).innerHTML</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">=</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">这段代码顺利被执行。</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">"</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 0, 0, 1)">;
</span><span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;</span><span style="color: rgba(128, 0, 0, 1)">strong</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注意:<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">strong</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span> 注释块不会被执行<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span></strong></span></pre>
</div>
<p>&nbsp;</p>
<p><span style="font-size: 16px; background-color: rgba(51, 204, 204, 1)"><strong>页面输出结果为：</strong></span></p>
<p><span style="font-size: 16px"><strong><img src="https://img2018.cnblogs.com/blog/1746290/201909/1746290-20190908155202828-1728576008.png" alt=""></strong></span></p>
<p>&nbsp;</p>
<p><span style="font-size: 16px"><strong>&nbsp;</strong></span></p>
<p><span style="font-size: 16px"><strong>⑵<span style="background-color: rgba(51, 204, 204, 1)">示例二</span>：在下面的例子中，注释用于阻止代码块的执行（可用于调试）：</strong></span></p>
<div class="cnblogs_code">
<pre><span style="font-size: 16px"><strong><span style="color: rgba(0, 0, 255, 1)">&lt;!</span><span style="color: rgba(255, 0, 255, 1)">DOCTYPE html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">meta </span><span style="color: rgba(255, 0, 0, 1)">charset</span><span style="color: rgba(0, 0, 255, 1)">="utf-8"</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释块不执行<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">title</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">head</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">h1 </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myH1"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">h1</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p </span><span style="color: rgba(255, 0, 0, 1)">id</span><span style="color: rgba(0, 0, 255, 1)">="myP"</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">/*</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">
document.getElementById("myH1").innerHTML="欢迎来到我的主页";
document.getElementById("myP").innerHTML="这是我的第一个段落。";
</span><span style="background-color: rgba(245, 245, 245, 1); color: rgba(0, 128, 0, 1)">*/</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">script</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;&lt;</span><span style="color: rgba(128, 0, 0, 1)">strong</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注意:<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">strong</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>注释块不会被执行。<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">p</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>

<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">body</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span>
<span style="color: rgba(0, 0, 255, 1)">&lt;/</span><span style="color: rgba(128, 0, 0, 1)">html</span><span style="color: rgba(0, 0, 255, 1)">&gt;</span></strong></span></pre>
</div>
<p>&nbsp;</p>
<p><span style="font-size: 16px; background-color: rgba(51, 204, 204, 1)"><strong>页面输出结果为：</strong></span></p>
<p><span style="font-size: 16px; background-color: rgba(51, 204, 204, 1)"><strong><img src="https://img2018.cnblogs.com/blog/1746290/201909/1746290-20190908155443285-1594537046.png" alt=""></strong></span></p>
<p>&nbsp;</p>
<p><span style="font-size: 16px"><strong>&nbsp;</strong></span></p>
<h2><span style="font-size: 18pt; color: rgba(255, 0, 0, 1)"><strong>㈣在行末使用注释</strong></span></h2>
<p><span style="font-size: 16px; color: rgba(255, 0, 0, 1)"><strong><span style="color: rgba(0, 0, 0, 1)">在下面的例子中，把注释放到代码行的结尾处：</span></strong></span></p>
<div class="cnblogs_code">
<pre><span style="font-size: 16px"><strong><span style="color: rgba(0, 0, 0, 1)">var x=5;    // 声明 x 并把 5 赋值给它
var y=x+2;// 声明 y 并把 x+2 赋值给它</span></strong></span></pre>
</div>
<p>&nbsp;</p>
<p><span style="font-size: 18pt; color: rgba(255, 0, 0, 1)"><strong>㈤注释的重要性</strong></span></p>
<p><span style="font-size: 16px"><strong>养成一个好的习惯就是写注释。</strong></span></p>
<p><span style="font-size: 16px"><strong>方便你二次阅读，维护你的代码。</strong></span></p>
<p><span style="font-size: 16px"><strong>如果后面项目转手，也方便别人来理解你的代码和维护你的代码。</strong></span></p>
<p>&nbsp;</p><br><br>
来源：https://www.cnblogs.com/shihaiying/p/11486878.html
頁: [1]
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