String.prototype.toLowerCase()

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since 2015年7月.

toLowerCase() 函式会回传将字符串转换为英文小写字母后的结果。

嘗試一下

const sentence = "The quick brown fox jumps over the lazy dog.";

console.log(sentence.toLowerCase());
// Expected output: "the quick brown fox jumps over the lazy dog."

语法

str.toLowerCase()

回传值

回传一组将原字串英文内容转换成英文小写字母后的结果。

描述

The toLowerCase() 函式会回传一组将原字符串英文内容转换成英文小写字母后的结果。 toLowerCase() 并不会影响到原字符串 str 的内容值。

范例

使用 toLowerCase()

console.log("ALPHABET".toLowerCase()); // 'alphabet'

规范

Specification

ECMAScript® 2027 Language Specification
# sec-string.prototype.tolowercase

浏览器相容性

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String.prototype.toLowerCase()

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