24模拟赛1

3. 迷惑的 this

handle() {
    this.inputEl.addEventListener('input',(e)=>{
      this.handleInput(e)
    })
}

这个回调的调用者是this也就是search对象

这样就不行：

handle() {
    // TODO：待补充代码  
    function deal(e) {
        this.handleInput(e)
    }
    this.inputEl.addEventListener('input',(e)=>{
        deal(e)
    })
},

原因：this指向调用者。

deal的调用者是一个箭头函数，而箭头函数的this是window。

（箭头函数不会创建自己的 this 上下文，所以 this 会在词法上指向外层的上下文，这里的外层上下文是全局上下文。）

4. 魔法失灵了

// 原先会响应式丢失
// let { value }={ ...data }

let { value }= toRefs( data)
// 返回的是ref，需要用.value

function update(val) {
    value.value = val
}

5. 燃烧你的卡路里

const sortItem = (arr, pro, compare) => {
    // TODO 根据 compare 匹配食材对象后返回这个对象
    arr.sort((a,b) => b[pro]-a[pro])
    for(let i=0;i<arr.length;i++){
        if(arr[i][pro]<=compare)
            return arr[i]
    }
};

6 司龄统计

考点：Echarts，动态属性名

// 按照年龄分组的函数
const groupByAge = (peoples) => {
  // 动态属性名（计算属性）
  const obj = {};
  peoples.forEach((element) => {
    let age = element.age;
    if (!obj[age]) {
      // if(!obj.age) 这样会查找`age`这个字符串
      obj[age] = [];
    }
    obj[age].push(element);
  });
  return obj;
};

const app = Vue.createApp({
  setup() {
    const { updateData } = useECharts();
    let xAxisData = Vue.ref([]); // X 轴数据，司龄从小到大排列
    let seriesData = Vue.ref([]); // Y 轴数据，司龄对应的人数
    const groupedPeople = Vue.ref([]); // table 中显示的数据
    Vue.onMounted(async () => {
      const data = await (await fetch("./mock/data.json")).json();
      groupedPeople.value = groupByAge(data); //把请求回来的数据变成需要的数据格式
      // TODO: 设置 Echars X 轴数据 xAxisData 和 Y 轴数据 seriesData
      xAxisData.value=Object.keys(groupedPeople.value)
      seriesData.value=Object.values(groupedPeople.value).map((item)=> item.length)
      // 更新 echars 数据
      updateData(xAxisData.value, seriesData.value);
    });

    return {
      groupedPeople,
    };
  },
});

app.mount("#app");

7 不翼而飞的余额

• store
• router

setup() {
    const depositAmount = Vue.ref() // 输入框中的的值->存款金额
    const store = useMoneyStore()  // 引入 store

    // TODO：待补充代码，完善点击存款按钮事件
    function deposit() {
        store.addDeposit(depositAmount.value)
        depositAmount.value=null
    }
    return {
        deposit,
        store,
        depositAmount
    }
}

const useMoneyStore = defineStore('money', () => {
    const balance = ref(23);
    const addDeposit=(add)=>{
      balance.value+=add
    }
    return {
      balance,addDeposit
    }
})

const { createPinia } = Pinia;
const { createRouter,createWebHistory } = VueRouter;  // TODO：待补充代码，在此引入路由相关 API 
const app = createApp({});
app.use(createPinia());

const router = createRouter({
    // TODO:待补充代码，为项目配置 history 模式的路由
    history:createWebHistory(), // createWebHashHistory
    routes:[
        {
            path:'/',
            component: WalletPage
        },
        {
            path:'/deposit',
            component: DepositPage 
        },
    ]
})

8 个性化推荐

const http = require("http");
const fs = require("fs");
const path = require("path");
const qs = require("querystring");
const data = require("../data.json");

const server = http.createServer((req, res) => {
  // 起始页路由处理
  if (req.url === "/") {
    // 读取 index.html 内容 如何读取文件
    const indexPage = fs.readFileSync(path.join(__dirname, "../index.html"), {
      encoding: "utf8",
    });

    // 将读取的 index.html 内容写入响应中，并返回给前端展示
    res.writeHead(200, { "Content-Type": "text/html" });
    res.write(indexPage);
    res.end();
  }
  // 个性化页面路由处理
  else if (req.url.startsWith("/customized")) {
    let body = "";
    req.on("data", (chunk) => {
      body += chunk;
    });

    req.on("end", () => {
      let { interested = [] } = qs.parse(body);
      // console.log(data);
      let result = "";
      if (interested.length===0) {
        // console.log(interested);
        result = `<div class="unselect">你还未选择任何感兴趣的标签！</div>`;
      } else {
        // 当interested只选了一个的时候，这会是一个字符串而不是数组
        if(! Array.isArray(interested)) interested=[interested]
        // console.log(interested, '\n 11111');
        const findContent = (target) => {
          for (const item of data) {
            if (item.tag == target) {
              return item;
            }
          }
          console.log("findContent");
        };

        const list = [];
        const set = new Set();
        // 枚举用户的兴趣列表
        for (const interest of interested) {
          // console.log(interest);
          const content = findContent(interest);
          list.push(content);
          set.add(content);
        }
        // console.log(list);
        // 读取相关兴趣
        for(const content of list){
          // continue
          // console.log(content); continue;
          if(!content.relevance.length) continue
          // C++的关联列表是空的，这里会报错
          for (const relevance of content.relevance) {
            const relevanceContent = findContent(relevance);
            if (!set.has(relevanceContent)) {
              list.push(relevanceContent);
              set.add(relevanceContent);
            }
          }
        }
        console.log(list);
        result=list.map((item)=> `<div class="interest">
                                      <div class="tag">${item.tag}</div>
                                      <div>${item.content}</div>
                                  </div>`).join('')      
      }
      let indexPage = fs.readFileSync(path.join(__dirname, "../customized.html"), {
        encoding: "utf8",
      });
      indexPage=indexPage.replace('<body></body>', `<body>` + result+`</body>`)
      res.write(indexPage)
      res.end();
    });
  }
});

server.listen(8080, () => {
  console.log("server is running in port 8080");
});

9 贪吃蛇

nextStep() {
    // TODO：待补充代码   
    // debugger
    for (let i = this.snakeBody.length - 1; i >= 1; i--) {
        this.snakeBody[i] = {
            ...this.snakeBody[i - 1]
        }
    }
    switch (this.direction) {
        case 'right':
            this.snakeBody[0].left += this.size
            break;
        case 'down':
            this.snakeBody[0].top += this.size
            break;
        case 'left':
            this.snakeBody[0].left -= this.size
            break;
        case 'up':
            this.snakeBody[0].top -= this.size
            break;
    }
    // debugger
    // 或者
    this.snakeBody.unshift(newHead);
    this.snakeBody.pop();
    // 结合unshift和pop，也能达到向后移动的效果
}

10 自定义表单验证器

watch(inputValue, (newValue) => {
      emit('update:modelValue', newValue)
    })

const is_email = (val) => {
  // TODO：目标 2 待补充代码
  let [before, behind] = val.split('@')

  // 没有@或@后面没有字母
  if (typeof(behind)!='string') return false
  let userReg = /[0-9a-zA-Z]+/
  if (!before.match(userReg)) return false

  let [firstBehind, lastBehind] = behind.split('.')
  let firstBehindReg = /^[0-9a-zA-Z]+$/
  if (!firstBehind.match(firstBehindReg)) return false

  let lastBehindReg = /^[0-9a-zA-Z]{2,4}$/
  if (!lastBehind.match(lastBehindReg)) return false
  console.log(111);
  return true
}

// FormValidator.js
for (let key in props.formData) {
  for (let rule of props.rules[key]) {
    // 若某个字段对应的错误信息为多个时，将按照验证规则数组的顺序优先显示，即只显示第一个错误信息。
    if (key in errors) break

    // rule有两种
    if ('validator' in rule) {
      rule.validator(rule, props.formData[key], (error) => {
        if (error) errors.value[key] = error.message;
      })
    } else {
      if ('required' in rule) {
        if (rule.required && props.formData[key] === '') {
          errors.value[key] = rule.message
        }
      }
      if ('type' in rule && rule.type === 'email') {
        if (!validateByType(rule.type, props.formData[key])
          || props.formData[key].length < 8 || props.formData[key].length > 20) {
          errors.value[key] = rule.message
        }
      }
    }
  }
}

冰墩墩心情刻度尺

https://www.lanqiao.cn/problems/6182/learning/?contest_id=149

https://www.lanqiao.cn/problems/6182/learning/?problem_list_id=24&page=1

  if (value === 0) BingDunDun.className = "BingDunDun not-satisfied";
  else if (value === 25) BingDunDun.className = "BingDunDun a-little-unsatisfied";
  else if (value === 50) BingDunDun.className = "BingDunDun ordinary";
  else if (value === 75) BingDunDun.className = "BingDunDun satisfied";
  else if (value === 100) BingDunDun.className = "BingDunDun great";


BingDunDun.className = `BingDunDun ${{0:'not-satisfied',25:'a-little-unsatisfied',50:'ordinary',75:'satisfied',100:'great'}[value]}`
  BingDunDun.className=`BingDunDun ${['not-satisfied','a-little-unsatisfied','ordinary','satisfied','great'][value/25]}`

会员卡定制

https://www.lanqiao.cn/problems/6190/learning/?problem_list_id=24&page=1

<span v-for="(n, $index) in otherCardMask" :key="$index">
  <transition name="slide-fade-up">
    <!-- 目标 1 TODO Start -->
    <!-- <div class="card-item__numberItem">{{n}}</div> -->
    <div
      v-if="cardNumber[$index] && (($index >4 && $index < 9)||($index >9 && $index < 14) ) "
      :class="['card-item__numberItem', {'-active': n===' '}]"
    >
      *
    </div>
    <div v-else-if="cardNumber[$index]" :class="['card-item__numberItem', {'-active': n===' '}]"
    >
      {{cardNumber[$index]}}
    </div>
    <div v-else :class="['card-item__numberItem', {'-active': n===' '}]">
      {{n}}
    </div>
  </transition>
</span>

<span
v-for="(n,id) in cardName.replace(/ +/g, ' ')"
class="card-item__nameItem"
:key="id"
>{{n.toUpperCase()}}</span
>

const minCardMonth = computed(() => {
  const date = new Date();
  if (data.cardYear != data.minCardYear) return 1;
  return date.getMonth() + 1;
});
watchEffect(
  // 都要监听到
  () => {
    if (minCardMonth.value > data.cardMonth) data.cardMonth = "";
    return data.cardYear; // 返回想要监听的响应式数据，ref 定义的数据需要返回其 value 属性
  },
  {
    immediate: true,
  }
);

比一比分大小

https://www.lanqiao.cn/problems/2290/learning/?contest_id=64

function orderStudentGrade(students) {
  // TODO: 在这里写入具体的实现逻辑
  // 将学生的成绩按班级分组，同一班级中按照总分从高到底排序
  let res = {};
  students.forEach((element) => {
    let classNo = element.class;
    if (classNo in res) {
      res[classNo].push(element);
    } else {
      res[classNo] = [element];
    }
  });
  console.log(res);
  for (let index in res) {
    res[index].sort(
      (a, b) =>b.math +b.language +b.english +b.physics +b.chemistry -
        a.math -a.language -a.english -a.physics -a.chemistry
    );
  }
  return res;
}

module.exports = orderStudentGrade; // 检测需要，请勿删除