/**
 * 计算两个数的和
 * @param {number} a 第一个加数
 * @param {number} b 第二个加数
 * @returns {number} 两数之和
 */
function add(a, b) {
  return a + b;
}

// 使用
console.log(add(1, 2)); // 输出: 3

// 定义一个接口来描述一个用户的属性
interface User {
  id: number;
  name: string;
  email: string;
  age?: number; // age是可选的
}

// 定义一个函数，接收一个User类型的参数
function greet(user: User) {
  return `Hello, ${user.name}!`;
}

// 使用可选属性创建一个用户对象
const user1: User = { id: 1, name: 'Alice', email: 'alice@example.com' };

// 使用完整属性创建另一个用户对象
const user2: User = { id: 2, name: 'Bob', email: 'bob@example.com', age: 30 };

// 调用函数并打印结果
console.log(greet(user1)); // 输出: Hello, Alice!
console.log(greet(user2)); // 输出: Hello, Bob!

import { Injectable, Scope } from '@nestjs/common';
import * as winston from 'winston';

@Injectable({ scope: Scope.TRANSIENT })
export class LoggingService {
  private logger: winston.Logger;

  constructor() {
    this.logger = winston.createLogger({
      level: 'info',
      format: winston.format.json(),
      transports: [
        new winston.transports.File({ filename: 'combined.log' }),
      ],
    });
  }

  logInfo(message: string) {
    this.logger.info(message);
  }

  logError(message: string) {
    this.logger.error(message);
  }
}

import { MouseEventHandler, KeyboardEventHandler, FocusEventHandler, FormEventHandler } from 'react';

// 示例1: 鼠标点击事件
const handleClick: MouseEventHandler<HTMLButtonElement> = (event) => {
  console.log(event.clientX, event.clientY);
};

// 示例2: 键盘按键事件
const handleKeyPress: KeyboardEventHandler<HTMLInputElement> = (event) => {
  console.log(event.key);
};

// 示例3: 输入框获得焦点事件
const handleFocus: FocusEventHandler<HTMLInputElement> = (event) => {
  console.log(event.target.value);
};

// 示例4: 表单提交事件
const handleSubmit: FormEventHandler<HTMLFormElement> = (event) => {
  event.preventDefault(); // 阻止表单默认提交行为
  console.log('Form submitted');
};

import { Controller, Get, Post, Body, Patch, Param, Delete } from '@nestjs/common';
import { ApiTags } from '@nestjs/swagger';
import { UsersService } from './users.service';
import { CreateUserDto } from './dto/create-user.dto';
import { UpdateUserDto } from './dto/update-user.dto';

@ApiTags('用户管理')
@Controller('users')
export class UsersController {
  constructor(private readonly usersService: UsersService) {}

  @Post()
  create(@Body() createUserDto: CreateUserDto) {
    return this.usersService.create(createUserDto);
  }

  @Get()
  findAll() {
    return this.usersService.findAll();
  }

  @Get(':id')
  findOne(@Param('id') id: string) {
    return this.usersService.findOne(+id);
  }

  @Patch(':id')
  update(@Param('id') id: string, @Body() updateUserDto: UpdateUserDto) {
    return this.usersService.update(+id, updateUserDto);
  }

  @Delete(':id')
  remove(@Param('id') id: string) {
    return this.usersService.remove(+id);
  }
}

// 定义装饰器工厂
function logClassMetadata(target: any) {
  console.log(`类名: ${target.name}`);
}

// 使用装饰器
@logClassMetadata
class MyClass {
  // 类的成员
}

// 执行上述装饰器后，会在控制台输出 MyClass 这个类名

module.exports = {
  root: true,
  parser: 'vue-eslint-parser',
  parserOptions: {
    parser: '@typescript-eslint/parser',
    sourceType: 'module'
  },
  extends: [
    'plugin:vue/vue3-recommended',
    'plugin:@typescript-eslint/recommended',
    'prettier/@typescript-eslint',
    'plugin:prettier/recommended'
  ],
  rules: {
    // 在这里添加或覆盖 ESLint 规则
  }
};

let value: unknown = 'Hello, World!';

let strLength = (value as string).length;

function isString(value: unknown): value is string {
  return typeof value === 'string';
}

let value: unknown = 'Hello, World!';

if (isString(value)) {
  console.log(value.toUpperCase());  // 在这里，TypeScript 知道 `value` 是一个字符串
}

<template>
  <el-menu
    :default-active="defaultActive"
    class="el-menu-vertical-demo"
    @open="handleOpen"
    @close="handleClose"
  >
    <template v-for="item in menuItems" :key="item.index">
      <el-sub-menu v-if="item.children && item.children.length" :index="item.index">
        <template #title>
          <i :class="item.icon"></i>
          <span>{{ item.title }}</span>
        </template>
        <side-menu-item
          v-for="subItem in item.children"
          :key="subItem.index"
          :item="subItem"
        />
      </el-sub-menu>
      <el-menu-item v-else :index="item.index">
        <i :class="item.icon"></i>
        <template #title>{{ item.title }}</template>
      </el-menu-item>
    </template>
  </el-menu>
</template>

<script lang="ts">
import { defineComponent, PropType } from 'vue';
import type { MenuItem } from './types';

export default defineComponent({
  name: 'SideMenu',
  props: {
    menuItems: {
      type: Array as PropType<MenuItem[]>,
      default: () => [],
    },
    defaultActive: {
      type: String,
      default: '',
    },
  },
  setup(props, { emit }) {
    const handleOpen = (index: string, indexPath: string) => {
      emit('open', index, indexPath);
    };

    const handleClose = (index: string, indexPath: string) => {
      emit('close', index, indexPath);
    };

    return {
      handleOpen,
      handleClose,
    };
  },
});
</script>

# 安装 Vite 工具
npm init vite@latest

# 运行上述命令后，按照提示进行操作
# 选择模板：vanilla
# 输入项目名称：my-vue-ts-project
# 选择框架：Vue
# 选择JavaScript框架：TypeScript
# 确认项目目录：确保目录正确

# 进入项目目录
cd my-vue-ts-project

# 安装依赖
npm install

# 启动开发服务器
npm run dev