基本用法

js中字符串的replace方法用于替換字符串中指定的字符，基本用法如下：

str.replace(regexp|substr, newSubStr|function)

let str = 'Tom is my best friend.'

let targ = str.replace('Tom', 'money')
console.log(targ) // 'money is my best friend'

然而，當(dāng)要替換的字符有多個(gè)時(shí)，上面方式往往只會(huì)替換第一個(gè)匹配到的字符。

let str = 'my friend is not your friend'

let targe = str.replace('friend', 'money')
console.log(targe) // 'my money is not your friend'

因此要全局替換時(shí)，需要使用正則

let str = 'my friend is not your friend'
// ①
let targe = str.replace(new RegExp('friend', 'g'), 'money')
// ②簡(jiǎn)寫(xiě)
let targe = str.replace(/friend/g, 'money')
console.log(targe) // 'my money is not your money'