`toISOString()` 方法返回一个 ISO（ISO 8601 Extended Format）格式的字符串： YYYY-MM-DDTHH:mm:ss.sssZ。时区总是UTC（协调世界时），加一个后缀“Z”标识。

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

## 语法

    dateObj.toISOString()

## 例子

    var today = new Date("05 October 2011 14:48 UTC");
    alert(today.toISOString()); // 返回2011-10-05T14:48:00.000Z

上例使用了非标准字符串的解析，该字符串在某些旧的浏览器（如IE）中可能无法被正确解析。

## Polyfill

该方法在ECMA-262第5版中被标准化。对于那些不支持此方法的JS引擎可以通过加上下面的代码实现：

    if ( !Date.prototype.toISOString ) {
      ( function() {

        function pad(number) {
          if ( number < 10 ) {
            return '0' + number;
          }
          return number;
        }

        Date.prototype.toISOString = function() {
          return this.getUTCFullYear() +
            '-' + pad( this.getUTCMonth() + 1 ) +
            '-' + pad( this.getUTCDate() ) +
            'T' + pad( this.getUTCHours() ) +
            ':' + pad( this.getUTCMinutes() ) +
            ':' + pad( this.getUTCSeconds() ) +
            '.' + (this.getUTCMilliseconds() / 1000).toFixed(3).slice(2, 5) +
            'Z';
        };

      }() );
    }

## 规范

规范版本 | 规范状态 | 注解
--- | --- | ---
ECMAScript 5.1 (ECMA-262) Date.prototype.toISOString Implemented in JavaScript 1.8 | Standard | Initial definition.
ECMAScript 2015 (6th Edition, ECMA-262) Date.prototype.toISOString | Standard |

## 浏览器兼容性

The compatibility table in this page is generated from structured data. If you'd like to contribute to the data, please check out https://github.com/mdn/browser-compat-data and send us a pull request.

Update compatibility data on GitHub

| Desktop | Mobile | Server
| Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | Android webview | Chrome for Android | Edge Mobile | Firefox for Android | Opera for Android | Safari on iOS | Samsung Internet | Node.js
`toISOString` | Chrome Full support Yes | Edge Full support 12 | Firefox Full support 1 | IE Full support 9 | Opera Full support Yes | Safari Full support Yes | WebView Android Full support Yes | Chrome Android Full support Yes | Edge Mobile Full support Yes | Firefox Android Full support 4 | Opera Android Full support Yes | Safari iOS Full support Yes | Samsung Internet Android Full support Yes | nodejs Full support Yes

### Legend

Full support
  Full support

## 相关链接

- `Date.prototype.toLocaleDateString()`
- `Date.prototype.toTimeString()`
- `Date.prototype.toUTCString()`