From 33058f2b292b3a581333bdfb21b8f671898c5060 Mon Sep 17 00:00:00 2001 From: Peter Bengtsson Date: Tue, 8 Dec 2020 14:40:17 -0500 Subject: initial commit --- .../global_objects/string/length/index.html | 135 +++++++++++++++++++++ 1 file changed, 135 insertions(+) create mode 100644 files/zh-cn/web/javascript/reference/global_objects/string/length/index.html (limited to 'files/zh-cn/web/javascript/reference/global_objects/string/length') diff --git a/files/zh-cn/web/javascript/reference/global_objects/string/length/index.html b/files/zh-cn/web/javascript/reference/global_objects/string/length/index.html new file mode 100644 index 0000000000..c51f812f6d --- /dev/null +++ b/files/zh-cn/web/javascript/reference/global_objects/string/length/index.html @@ -0,0 +1,135 @@ +--- +title: String.length +slug: Web/JavaScript/Reference/Global_Objects/String/length +tags: + - JavaScript + - Property + - Prototype + - String +translation_of: Web/JavaScript/Reference/Global_Objects/String/length +--- +

{{JSRef("Global_Objects", "String")}}

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概述

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length 属性表示一个字符串的长度。

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描述

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该属性返回字符串中字符编码单元的数量。JavaScript 使用 {{ interwiki("wikipedia", "UTF-16") }} 编码，该编码使用一个 16 比特的编码单元来表示大部分常见的字符，使用两个代码单元表示不常用的字符。因此 length 返回值可能与字符串中实际的字符数量不相同。

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空字符串的 length 为 0。

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静态属性 String.length 返回 1。

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示例

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var x = "Mozilla";
+var empty = "";
+
+console.log("Mozilla is " + x.length + " code units long");
+/* "Mozilla is 7 code units long" */
+
+console.log("The empty string is has a length of " + empty.length);
+/* "The empty string is has a length of 0" */
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规范

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SpecificationStatusComment
{{SpecName('ES1')}}{{Spec2('ES1')}}Initial definition. Implemented in JavaScript 1.0.
{{SpecName('ES5.1', '#sec-15.5.5.1', 'String.prototype.length')}}{{Spec2('ES5.1')}} 
{{SpecName('ES6', '#sec-properties-of-string-instances-length', 'String.prototype.length')}}{{Spec2('ES6')}} 
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浏览器兼容性

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{{ CompatibilityTable() }}

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FeatureChromeFirefox (Gecko)Internet ExplorerOperaSafari
Basic support{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}
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FeatureAndroidChrome for AndroidFirefox Mobile (Gecko)IE MobileOpera MobileSafari Mobile
Basic support{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}{{ CompatVersionUnknown() }}
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相关链接

+ + -- cgit v1.2.3-54-g00ecf