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docs/javascript/Reference/Global_Objects/Number.html
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<div></div>
<p> JavaScript 的 <strong><code>Number</code></strong> 对象是经过封装的能让你处理数字值的对象。<code>Number</code> 对象由 <code>Number()</code> 构造器创建。</p>
<h2 id="Syntax" name="Syntax">语法</h2>
<pre class="syntaxbox">new Number(value);</pre>
<pre><code class="language-javascript">new Number(value);</code></pre>
<h3 id="Parameters" name="Parameters">参数</h3>
<dl>
<dt><code>value</code></dt>
@@ -78,31 +78,31 @@
<h2 id="Examples" name="Examples">示例</h2>
<h3 id="Example:_Using_the_Number_object_to_assign_values_to_numeric_variables" name="Example:_Using_the_Number_object_to_assign_values_to_numeric_variables">使用 Number 对象给数字变量赋值</h3>
<p>下例使用 <code>Number</code> 对象的属性给几个数字变量赋值：</p>
<pre class="brush: js">var biggestNum = Number.MAX_VALUE;
<pre><code class="language-javascript">var biggestNum = Number.MAX_VALUE;
var smallestNum = Number.MIN_VALUE;
var infiniteNum = Number.POSITIVE_INFINITY;
var negInfiniteNum = Number.NEGATIVE_INFINITY;
var notANum = Number.NaN;
</pre>
</code></pre>
<h3 id="整数类型的范围">整数类型的范围</h3>
<p>下例展示了<code>Number</code>对象所能表示的最大和最小整数 (详情请参阅 ECMAScript standard, chapter <em>8.5 The Number Type</em>):</p>
<pre class="brush: js">var biggestInt = 9007199254740992;
var smallestInt = -9007199254740992;</pre>
<pre><code class="language-javascript">var biggestInt = 9007199254740992;
var smallestInt = -9007199254740992;</code></pre>
<p>在解析序列化的JSON时，如果JSON解析器将它们强制转换为Number类型，那么超出此范围的整数值可能会被破坏。在工作中使用<a href="Reference/String" title="此页面仍未被本地化, 期待您的翻译!"><code>String</code></a> 类型代替，是一个可行的解决方案。</p>
<h3 id="Example:_Using_Number_to_convert_a_Date_object" name="Example:_Using_Number_to_convert_a_Date_object">使用 <code>Number</code> 转换 <code>Date</code> 对象</h3>
<p>下例使用 Number 作为函数来转换 <code>Date</code> 对象为数字值：</p>
<pre class="brush: js">var d = new Date("December 17, 1995 03:24:00");
<pre><code class="language-javascript">var d = new Date("December 17, 1995 03:24:00");
print(Number(d));
</pre>
</code></pre>
<p>这将输出 "819199440000"。</p>
<h3 id="转换数字字符串为数字">转换数字字符串为数字</h3>
<pre class="brush: js">Number("123") // 123
<pre><code class="language-javascript">Number("123") // 123
Number("") // 0
Number("0x11") // 17
Number("0b11") // 3
Number("0o11") // 9
Number("foo") // NaN
Number("100a") // NaN</pre>
Number("100a") // NaN</code></pre>
<h2 id="Specifications">Specifications</h2>
<table class="standard-table">
<tbody>