如何实现以下字符串操作？ [关闭]

Question

我在JS中有以下场景，如何才能达到JS所示的预期结果：

var a = "Track ABCD Evac - The New World [ARQ:1630564] [ Deleted:false]";
var b = "Track Evogue Evac - The Jerry [FRQ:1630315] [ Deleted:false]";
var c = "Track YRF Evac - The Marvels [DRQ:1630334] [ Deleted:false]";

预期输出：

一个= ARQ

b = 频率

c = 需求请求

Answer 1

// Input params.
const a = "Track ABCD Evac - The New World [ARQ:1630564] [ Deleted:false]";
const b = "Track Evogue Evac - The Jerry [FRQ:1630315] [ Deleted:false]";
const c = "Track YRF Evac - The Marvels [DRQ:1630334] [ Deleted:false]";

// Normalization function.
const normalize = str => str.substring(str.indexOf('[') + 1, str.indexOf(':'));

// Log normalized results.
console.log(normalize(a));
console.log(normalize(b));
console.log(normalize(c));