How to use Javascript metacharacters

Instructions

1. Metacharacters can use [a-z] to search for all letters in the alphabet. This metacharacter is more common and has an abbreviation, the eager abbreviation also contains extra characters.

2. The closest metacharacter matching the alphabet is \w. This abbreviation is equivalent to [A-Za-z0-9_]. This character class matches uppercase and lowercase letters as well as numbers.

Note that this character class also contains the underscore character (_).

Example

要求
使用元字符 \w 来计算所有引号中字母和数字字符的数量。
let quoteSample = "The five boxing wizards jump quickly.";
let alphabetRegexV2 = /change/; // 修改这一行
let result = quoteSample.match(alphabetRegexV2).length;
 
参考
let quoteSample = "The five boxing wizards jump quickly.";
let alphabetRegexV2 = /\w/g; // 修改这一行
let result = quoteSample.match(alphabetRegexV2).length;

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