path: root/files/zh-cn/web/javascript/reference/global_objects/int32array/index.html

---
title: Int32Array
slug: Web/JavaScript/Reference/Global_Objects/Int32Array
translation_of: Web/JavaScript/Reference/Global_Objects/Int32Array
---
<div>{{JSRef}}</div>

<p>该 <strong><code>Int32Array</code></strong> 类型表示在平台顺序字节中一个双补码32位有符号的整型数组。如果需要控制字节顺序，请改用{{jsxref("DataView")}} 。此内容的初始化为<code>0</code>。一旦创建，你可以使用对象的方法或者标准数组索引的语法(即使用括号表示法)。</p>

<h2 id="语法">语法</h2>

<pre class="syntaxbox">new Int32Array(length);
new Int32Array(typedArray);
new Int32Array(object);
new Int32Array(buffer [, byteOffset [, length]]);</pre>

<p>更多关于构造函数语法和参数的详细信息，请参阅<em><a href="/en-US/docs/Web/JavaScript/Reference/Global_Objects/TypedArray#Syntax">TypedArray</a>。</em></p>

<h2 id="属性">属性</h2>

<dl>
 <dt>{{jsxref("TypedArray.BYTES_PER_ELEMENT", "Int32Array.BYTES_PER_ELEMENT")}}</dt>
 <dd>Returns a number value of the element size. <code>4</code> in the case of an <code>Int32Array</code>.   </dd>
 <dt>Int32Array.length</dt>
 <dd>Static length property whose value is 3. For the actual length (number of elements), see {{jsxref("TypedArray.prototype.length", "Int32Array.prototype.length")}}.</dd>
 <dt>{{jsxref("TypedArray.name", "Int32Array.name")}}</dt>
 <dd>Returns the string value of the constructor name. In the case of the <code>Int32Array</code> type: "Int32Array".</dd>
 <dt>{{jsxref("TypedArray.prototype", "Int32Array.prototype")}}</dt>
 <dd>Prototype for the <em>TypedArray</em> objects.</dd>
</dl>

<h2 id="方法">方法</h2>

<dl>
 <dt>{{jsxref("TypedArray.from", "Int32Array.from()")}}</dt>
 <dd>从类似数组或者可迭代对象中创建一个新的<code>Int32Array</code>。另见{{jsxref("Array.from()")}}.</dd>
 <dt>{{jsxref("TypedArray.of", "Int32Array.of()")}}</dt>
 <dd>创建一个新的具有可变数量参数的<code>Int32Array</code>。另见{{jsxref("Array.of()")}}。</dd>
</dl>

<h2 id="Int32Array_属性"><code>Int32Array</code> 属性</h2>

<p>所有的<code>Int32Array</code>对象都继承自{jsxref("TypedArray.prototype", "%TypedArray%.prototype")}}。</p>

<h3 id="属性_2">属性</h3>

<dl>
 <dt><code>Int32Array.prototype.constructor</code></dt>
 <dd>返回创建实例原型的函数。默认情况下,它是<code>Int32Array</code>的构造函数。</dd>
 <dt>{{jsxref("TypedArray.prototype.buffer", "Int32Array.prototype.buffer")}} {{readonlyInline}}</dt>
 <dd>返回在构造时被固定的<code>Int32Array</code>引用的{{jsxref("ArrayBuffer")}}，因此只读。</dd>
 <dt>{{jsxref("TypedArray.prototype.byteLength", "Int32Array.prototype.byteLength")}} {{readonlyInline}}</dt>
 <dd>返回从其{{jsxref("ArrayBuffer")}}开始的<code>Int32Array</code>长度的(以字节为单位)。在构造时被固定，因此只读。</dd>
 <dt>{{jsxref("TypedArray.prototype.byteOffset", "Int32Array.prototype.byteOffset")}} {{readonlyInline}}</dt>
 <dd>返回从其{{jsxref("ArrayBuffer")}}开始的偏移量(以字节为单位)。在构造时被固定,因此只读。</dd>
</dl>

<dl>
 <dt>{{jsxref("TypedArray.prototype.length", "Int32Array.prototype.length")}} {{readonlyInline}}</dt>
 <dd>     返回<code>Int32ArrayInt32Array</code>包含的元素个数。在构造时被固定,因此只读。</dd>
</dl>

<h3 id="方法_2">方法</h3>

<dl>
 <dt>{{jsxref("TypedArray.copyWithin", "Int32Array.prototype.copyWithin()")}}</dt>
 <dd>Copies a sequence of array elements within the array. See also {{jsxref("Array.prototype.copyWithin()")}}.</dd>
 <dt>{{jsxref("TypedArray.entries", "Int32Array.prototype.entries()")}}</dt>
 <dd>Returns a new <code>Array Iterator</code> object that contains the key/value pairs for each index in the array. See also {{jsxref("Array.prototype.entries()")}}.</dd>
 <dt>{{jsxref("TypedArray.every", "Int32Array.prototype.every()")}}</dt>
 <dd>Tests whether all elements in the array pass the test provided by a function. See also {{jsxref("Array.prototype.every()")}}.</dd>
 <dt>{{jsxref("TypedArray.fill", "Int32Array.prototype.fill()")}}</dt>
 <dd>Fills all the elements of an array from a start index to an end index with a static value. See also {{jsxref("Array.prototype.fill()")}}.</dd>
 <dt>{{jsxref("TypedArray.filter", "Int32Array.prototype.filter()")}}</dt>
 <dd>Creates a new array with all of the elements of this array for which the provided filtering function returns true. See also {{jsxref("Array.prototype.filter()")}}.</dd>
 <dt>{{jsxref("TypedArray.find", "Int32Array.prototype.find()")}}</dt>
 <dd>Returns the found value in the array, if an element in the array satisfies the provided testing function or <code>undefined</code> if not found. See also {{jsxref("Array.prototype.find()")}}.</dd>
 <dt>{{jsxref("TypedArray.findIndex", "Int32Array.prototype.findIndex()")}}</dt>
 <dd>Returns the found index in the array, if an element in the array satisfies the provided testing function or -1 if not found. See also {{jsxref("Array.prototype.findIndex()")}}.</dd>
 <dt>{{jsxref("TypedArray.forEach", "Int32Array.prototype.forEach()")}}</dt>
 <dd>Calls a function for each element in the array. See also {{jsxref("Array.prototype.forEach()")}}.</dd>
 <dt>{{jsxref("TypedArray.includes", "Int32Array.prototype.includes()")}} {{experimental_inline}}</dt>
 <dd>Determines whether a typed array includes a certain element, returning <code>true</code> or <code>false</code> as appropriate. See also {{jsxref("Array.prototype.includes()")}}.</dd>
 <dt>{{jsxref("TypedArray.indexOf", "Int32Array.prototype.indexOf()")}}</dt>
 <dd>Returns the first (least) index of an element within the array equal to the specified value, or -1 if none is found. See also {{jsxref("Array.prototype.indexOf()")}}.</dd>
 <dt>{{jsxref("TypedArray.join", "Int32Array.prototype.join()")}}</dt>
 <dd>Joins all elements of an array into a string. See also {{jsxref("Array.prototype.join()")}}.</dd>
 <dt>{{jsxref("TypedArray.keys", "Int32Array.prototype.keys()")}}</dt>
 <dd>Returns a new <code>Array Iterator</code> that contains the keys for each index in the array. See also {{jsxref("Array.prototype.keys()")}}.</dd>
 <dt>{{jsxref("TypedArray.lastIndexOf", "Int32Array.prototype.lastIndexOf()")}}</dt>
 <dd>Returns the last (greatest) index of an element within the array equal to the specified value, or -1 if none is found. See also {{jsxref("Array.prototype.lastIndexOf()")}}.</dd>
 <dt>{{jsxref("TypedArray.map", "Int32Array.prototype.map()")}}</dt>
 <dd>Creates a new array with the results of calling a provided function on every element in this array. See also {{jsxref("Array.prototype.map()")}}.</dd>
 <dt>{{jsxref("TypedArray.move", "Int32Array.prototype.move()")}} {{non-standard_inline}} {{unimplemented_inline}}</dt>
 <dd>Former non-standard version of {{jsxref("TypedArray.copyWithin", "Int32Array.prototype.copyWithin()")}}.</dd>
 <dt>{{jsxref("TypedArray.reduce", "Int32Array.prototype.reduce()")}}</dt>
 <dd>Apply a function against an accumulator and each value of the array (from left-to-right) as to reduce it to a single value. See also {{jsxref("Array.prototype.reduce()")}}.</dd>
 <dt>{{jsxref("TypedArray.reduceRight", "Int32Array.prototype.reduceRight()")}}</dt>
 <dd>Apply a function against an accumulator and each value of the array (from right-to-left) as to reduce it to a single value. See also {{jsxref("Array.prototype.reduceRight()")}}.</dd>
 <dt>{{jsxref("TypedArray.reverse", "Int32Array.prototype.reverse()")}}</dt>
 <dd>Reverses the order of the elements of an array — the first becomes the last, and the last becomes the first. See also {{jsxref("Array.prototype.reverse()")}}.</dd>
 <dt>{{jsxref("TypedArray.set", "Int32Array.prototype.set()")}}</dt>
 <dd>在类型化数组中存储多个值，从指定数组中读取输入值。</dd>
 <dt>{{jsxref("TypedArray.slice", "Int32Array.prototype.slice()")}}</dt>
 <dd>提取数组中的一部分，并返回一个新的数组.更多请见{{jsxref("Array.prototype.slice()")}}。</dd>
 <dt>{{jsxref("TypedArray.some", "Int32Array.prototype.some()")}}</dt>
 <dd>如果数组中至少有一个元素满足所提供的测试函数，则返回true。更多请见{{jsxref("Array.prototype.some()")}}。</dd>
 <dt>{{jsxref("TypedArray.sort", "Int32Array.prototype.sort()")}}</dt>
 <dd>Sorts the elements of an array in place and returns the array. See also {{jsxref("Array.prototype.sort()")}}.</dd>
 <dt>{{jsxref("TypedArray.subarray", "Int32Array.prototype.subarray()")}}</dt>
 <dd>Returns a new <code>Int32Array</code> from the given start and end element index.</dd>
 <dt>{{jsxref("TypedArray.values", "Int32Array.prototype.values()")}}</dt>
 <dd>Returns a new <code>Array Iterator</code> object that contains the values for each index in the array. See also {{jsxref("Array.prototype.values()")}}.</dd>
 <dt>{{jsxref("TypedArray.toLocaleString", "Int32Array.prototype.toLocaleString()")}}</dt>
 <dd>Returns a localized string representing the array and its elements. See also {{jsxref("Array.prototype.toLocaleString()")}}.</dd>
 <dt>{{jsxref("TypedArray.toString", "Int32Array.prototype.toString()")}}</dt>
 <dd>Returns a string representing the array and its elements. See also {{jsxref("Array.prototype.toString()")}}.</dd>
 <dt>{{jsxref("TypedArray.@@iterator", "Int32Array.prototype[@@iterator]()")}}</dt>
 <dd>Returns a new <code>Array Iterator</code> object that contains the values for each index in the array.</dd>
</dl>

<h2 id="例子">例子</h2>

<p>不同的方式创建一个 <code>Int32Array</code></p>

<pre class="brush: js">// 从一个数字
var int32 = new Int32Array(2);
int32[0] = 42;
console.log(int32[0]); // 42
console.log(int32.length); // 2
console.log(int32.BYTES_PER_ELEMENT); // 4

// 从一个数组
var arr = new Int32Array([21,31]);
console.log(arr[1]); // 31

// 从一个其他TypedArray
var x = new Int32Array([21, 31]);
var y = new Int32Array(x);
console.log(y[0]); // 21

// 从一个ArrayBuffer
var buffer = new ArrayBuffer(16);
var z = new Int32Array(buffer, 0, 4);
</pre>

<h2 id="详细描述">详细描述</h2>

<table class="standard-table">
 <tbody>
  <tr>
   <th scope="col">Specification</th>
   <th scope="col">Status</th>
   <th scope="col">Comment</th>
  </tr>
  <tr>
   <td>{{SpecName('Typed Array')}}</td>
   <td>{{Spec2('Typed Array')}}</td>
   <td>已被ECMAScript 6取代.</td>
  </tr>
  <tr>
   <td>{{SpecName('ES6', '#table-49', 'TypedArray constructors')}}</td>
   <td>{{Spec2('ES6')}}</td>
   <td>ECMA标准中的初始定义，指定需要新建。</td>
  </tr>
  <tr>
   <td>{{SpecName('ESDraft', '#table-49', 'TypedArray constructors')}}</td>
   <td>{{Spec2('ESDraft')}}</td>
   <td> </td>
  </tr>
 </tbody>
</table>

<h2 id="浏览器兼容性">浏览器兼容性</h2>

<p>{{CompatibilityTable}}</p>

<div id="compat-desktop">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Chrome</th>
   <th>Firefox (Gecko)</th>
   <th>Internet Explorer</th>
   <th>Opera</th>
   <th>Safari</th>
  </tr>
  <tr>
   <td>基本支持</td>
   <td>7.0</td>
   <td>{{ CompatGeckoDesktop(2) }}</td>
   <td>10</td>
   <td>11.6</td>
   <td>5.1</td>
  </tr>
  <tr>
   <td>新 的特性</td>
   <td>{{CompatUnknown}}</td>
   <td>{{ CompatGeckoDesktop(44) }}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
 </tbody>
</table>
</div>

<div id="compat-mobile">
<table class="compat-table">
 <tbody>
  <tr>
   <th>Feature</th>
   <th>Android</th>
   <th>Chrome for Android</th>
   <th>Firefox Mobile (Gecko)</th>
   <th>IE Mobile</th>
   <th>Opera Mobile</th>
   <th>Safari Mobile</th>
  </tr>
  <tr>
   <td>基本支持</td>
   <td>4.0</td>
   <td>{{CompatVersionUnknown}}</td>
   <td>{{ CompatGeckoMobile(2) }}</td>
   <td>10</td>
   <td>11.6</td>
   <td>4.2</td>
  </tr>
  <tr>
   <td><code>新</code>的特性</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{ CompatGeckoMobile(44) }}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
   <td>{{CompatUnknown}}</td>
  </tr>
 </tbody>
</table>
</div>

<h2 id="兼容性说明">兼容性说明</h2>

<p>Starting with ECMAScript 2015 (ES6), <code>In32Array</code> constructors require to be constructed with a {{jsxref("Operators/new", "new")}} operator. Calling a <code>Int32Array</code> constructor as a function without <code>new</code>, will throw a {{jsxref("TypeError")}} from now on.</p>

<pre class="brush: js example-bad">var dv = Int32Array([1, 2, 3]);
// TypeError: calling a builtin Int32Array constructor
// without new is forbidden</pre>

<pre class="brush: js example-good">var dv = new Int32Array([1, 2, 3]);</pre>

<h2 id="参见">参见</h2>

<ul>
 <li><a href="/en-US/docs/Web/JavaScript/Typed_arrays" title="en/JavaScript typed arrays">JavaScript typed arrays</a></li>
 <li>{{jsxref("ArrayBuffer")}}</li>
 <li>{{jsxref("DataView")}}</li>
</ul>