librz

export function getErrorMessage(err: unknown, defaultMessage = "An error occurred") {
  if (err instanceof Error && err.message) {
    return err.message;
  }
  if (err instanceof Object && "message" in err && typeof err.message === "string" && err.message) {
    return err.message;
  }
  if (typeof err === "string" && err) {
    return err;
  }

librz

In TypeScript, u can easily declare constants using as const:

const Meal = {
  Breakfast: 'breakfast',
  Lunch: 'lunch',
  Dinner: 'dinner'
}

librz

import { useState } from "react";
import { useBeforeUnload, useBlocker } from "react-router-dom";

// unstable_usePrompt: https://reactrouter.com/en/main/hooks/use-prompt
// useBlocker: https://reactrouter.com/en/main/hooks/use-blocker
// useBeforeUnload: https://reactrouter.com/en/main/hooks/use-before-unload

export default function Form() {
  const [input, setInput] = useState("");

librz

/**
 * 以下代码来自 react-router-dom v6，用于解决 react-router-dom v5 没有 useSearchParams 的问题
 * see: https://github.com/remix-run/react-router/blob/main/packages/react-router-dom/index.tsx#L1432
 * 在原代码的基础上做的改动:
 * 1. 原代码使用了 useNavigate，但 react-router v5 还没有这个 hook，使用 useHistory 代替(https://reactrouter.com/en/main/upgrading/v5#use-usenavigate-instead-of-usehistory)
 * 2. 在返回的数组中提供 updateSearchParams 以在保留其他参数的情况下设置/更新指定的参数
 */

import React, { useCallback } from 'react';
import { useLocation, useHistory } from 'react-router';

librz

const list = [
  { province: '天津', city: '南开', district: '三马路' },
  {
    province: '天津',
    city: '南开',
    district: '四马路'
  },
  {
    province: '天津',
    city: '河西',

librz

/*
note: this is not a general purpose crawling script & can be only used as a reference
background:
1. target site has a side bar which contains many level-1 menus, each level-1 menu contains many level-2 menus
2. level-1 menu stores category name; level-2 menu stores system name, upon click will fire related event & load content as an iframe
*/

const sideMenu = document.querySelector("#side-menu");
const menus = Array.from(sideMenu.querySelectorAll(":scope > li:has(> ul.mm-collapse)"));

librz

// this script does not handle file suffix for you
// as some files have multiple suffix segments, e.g: *.sc.ass & *.tc.ass are two common subtitle formats
// instead, you should manually specify suffix in regex as the last capture group

const fs = require("fs")

const isDryrun = !process.argv.includes("-r");

if (isDryrun) {
	console.log("Note: By default, this script will only dry run, specify -r if you want to actually run it.")

librz

<section className="h-full w-full flex justify-center items-center gap-8 p-6 flex-col md:flex-row">
  <div className="rounded-full w-36 h-36 bg-black font-semibold flex justify-center items-center text-6xl text-white">
    404
  </div>
  <div className="flex flex-col items-end">
    <div className="text-5xl">Oops</div>
    <div className="text-2xl mt-2 mb-6 text-end">This page doesn't exist</div>
    <span className="bg-black text-white px-4 py-2 rounded-md cursor-pointer">
      Home
    </span>

librz

import { FallbackProps } from "react-error-boundary";
import React, { CSSProperties } from "react";

const ErrorFallback: React.ComponentType<FallbackProps> = ({
  error,
  resetErrorBoundary,
}) => {
  const sectionStyle: CSSProperties = {
    display: "flex",
    flexDirection: "column",

librz

function check() {
  const minimalUserResponseInMiliseconds = 200;
  console.clear();
  let before = new Date().getTime();
  debugger;
  let after = new Date().getTime();
  if (after - before > minimalUserResponseInMiliseconds) {
    document.write(" Don't open Developer Tools.");
    window.location.reload();
  }