<li class="ct-li" v-for="list in checkdData" :style="{ fontSize: sliderValue + 'px' }"> <div class="ct-li-wrap"> <span>{{ list.index }} 、</span> <div class="ct-li-info"> <p>排号： <span>{{list.UserId}}</span> &nbsp;&nbsp; <span>{{processName(list.name) }}</span> &nbsp;&nbsp; <span v-if="list.States === '过号' " :key="list.index" :style="list.States === '过号' ? 'color: red;' : ''">（过号）</span> </p> <p>{{ list.Djlsh }}</p> </div> </div> </li><input type="text" placeholder=" 输入流水号回车" class="input-ct" v-model="inputDrValues" @keydown.enter="onEnters"/>mounted() { this.grilData(); this.manData(); setInterval(() => { this.grilData(); // 每5秒获取一次数据 this.manData(); }, 500000); },async onEnter(){ try{ const roomnumber = '03'; const djlsh = this.inputValue; const isExist = this.matchedData.some(data => data.Djlsh === djlsh); if(!isExist){ const url = getCt(); const CTData = await fetchCt(url, roomnumber,djlsh ); //排队完成 this.couter1++; this.matchedData.push(CTData); this.inputValue=''; }else{ console.log("该流水号输入过") } }catch(e){ console.log("排队失败"); } },async grilData(){ try{ const gender = '0'; const roomnumber = '03'; // const urls = getCtUrl(); // const CTDatas= await fetchLine(urls,roomnumber,gender); const response = await axios.get('/line.json'); //女生数据 const CTDatas = response.data; console.log("CTDatas",CTDatas); //让获得的数据按顺序来排 this.matchedData = CTDatas.data.list.filter(data => data.States !== "正在检").map((data, index) => { data.index = index +1 ; // this.couter1++; // 计数器递增 return data; }); this.matchedData.forEach(data => { if (data.States === '叫号') { console.log("叫号",data); this.startSpeech({...data, RoomNumber: roomnumber}); } }); }catch(e){ console.log("获取数据库信息失败"); } },processName(name) { if (name.length === 2) { return name[0] + '*'; } else if (name.length === 3) { return name[0] + '*' + name[2]; } else { return name; } },为什么会显示Uncaught (in promise) TypeError: name is undefined

根据你提供的代码，在`processName`方法中可能会抛出`Uncaught (in promise) TypeError: name is undefined`错误的原因是`name`参数未定义。可能是在某些情况下，传入的`name`参数为`undefined`。

为了解决这个问题，你可以在调用`processName`方法之前添加一个条件判断来检查`name`是否存在。如果`name`不存在，你可以返回一个空字符串或其他默认值。

下面是修改后的代码示例：

processName(name) {
  if (!name) {
    return ''; // 或者返回其他默认值
  }
  if (name.length === 2) {
    return name[0] + '*';
  } else if (name.length === 3) {
    return name[0] + '*' + name[2];
  } else {
    return name;
  }
}

通过添加条件判断，当`name`不存在时，不再执行后续的操作，避免了抛出错误。这样修改后，你就不会再遇到`Uncaught (in promise) TypeError: name is undefined`错误了。

相关问题

<main-content :ifDetail="true"> <div class="two-side"> <div class="main-left"> <el-form :model="form" :rules="rules" ref="form" label-width="120px"> <el-form-item label="选择下载模块" prop="accountName"> <el-input v-model.trim="form.accountName" :maxlength="50"></el-input> </el-form-item> <el-form-item label="倾斜度"> <el-slider v-model.number="form.rotate" :min="-180" :max="180"></el-slider> </el-form-item> <el-form-item label="文字"> <el-input type="textarea" v-model="form.text"></el-input> </el-form-item> <el-form-item label="文字大小"> <el-input-number v-model.number="form.fontSize" :min="10" :max="50"></el-input-number> px </el-form-item> <el-form-item label="位置"> <el-select placeholder="请选择位置" v-model="form.alignment"> <el-option v-for="item in options" :key="item.value" :label="item.label" :value="item.value"></el-option> </el-select> </el-form-item> <el-form-item> <el-select v-if="form.alignment === 2" placeholder="请选择位置" v-model="form.textPosition"> <el-option v-for="item in textPositionOptions" :key="item.value" :label="item.label" :value="item.value" ></el-option> </el-select> </el-form-item> </el-form> {{ watermarkStyle }} </div> <div class="main-right" id="show"> <div class="watermark"> <span :style="watermarkStyle" ref="showText" style="word-break:break-all;display: inline-block">{{ form.text }}</span> </div> </div> </div> </main-content> 左边来控制右边div里水印展示，代码怎么写

您可以在 `<el-form>` 标签上绑定 `@input` 事件，当表单数据发生改变时，触发该事件，然后在事件处理函数中计算出水印的样式，并将样式绑定到 `<span>` 标签上。具体实现代码如下：

<template>
  <main-content :ifDetail="true">
    <div class="two-side">
      <div class="main-left">
        <el-form :model="form" :rules="rules" ref="form" label-width="120px" @input="handleInput">
          <!-- 表单项省略 -->
        </el-form>
      </div>
      <div class="main-right" id="show">
        <div class="watermark">
          <span :style="watermarkStyle" ref="showText" style="word-break:break-all;display: inline-block">{{ form.text }}</span>
        </div>
      </div>
    </div>
  </main-content>
</template>

<script>
export default {
  data() {
    return {
      form: {
        accountName: '',
        rotate: 0,
        text: '',
        fontSize: 16,
        alignment: 1,
        textPosition: 1
      },
      options: [
        { label: '左上', value: 1 },
        { label: '居中', value: 2 },
        { label: '右下', value: 3 }
      ],
      textPositionOptions: [
        { label: '正常', value: 1 },
        { label: '斜体', value: 2 }
      ]
    }
  },
  computed: {
    watermarkStyle() {
      const { rotate, fontSize, alignment, textPosition } = this.form
      const deg = rotate + (textPosition === 2 ? -45 : 0)
      const translateX =
        alignment === 1 ? '-10%' : alignment === 2 ? '-50%' : '90%'
      const translateY =
        alignment === 1 ? '-10%' : alignment === 2 ? '-50%' : '90%'
      const transform = `rotate(${deg}deg)`
      const style = {
        position: 'absolute',
        top: 0,
        left: 0,
        bottom: 0,
        right: 0,
        fontSize: `${fontSize}px`,
        transform: transform,
        '-webkit-transform': transform,
        '-ms-transform': transform,
        '-moz-transform': transform,
        '-o-transform': transform,
        opacity: '0.2',
        'pointer-events': 'none',
        'text-align': 'center',
        'z-index': 9999,
        transformOrigin: '50% 50%',
        '-webkit-transform-origin': '50% 50%',
        '-ms-transform-origin': '50% 50%',
        '-moz-transform-origin': '50% 50%',
        '-o-transform-origin': '50% 50%',
        color: '#000',
        'word-break': 'break-all',
        'white-space': 'pre-wrap',
        'max-height': '100%',
        'max-width': '100%',
        overflow: 'hidden',
        'text-overflow': 'ellipsis',
        '-webkit-text-fill-color': 'transparent',
        '-webkit-background-clip': 'text',
        'background-clip': 'text',
        '-webkit-user-select': 'none',
        '-moz-user-select': 'none',
        '-ms-user-select': 'none',
        userSelect: 'none',
        '-webkit-line-clamp': '1',
        display: 'flex',
        'align-items': 'center',
        'justify-content': 'center',
        'transform-style': 'preserve-3d'
      }
      if (textPosition === 2) {
        style.padding = '0.5rem'
        style.background =
          'linear-gradient(to right bottom, rgba(255, 255, 255, 0.2) 0%, rgba(255, 255, 255, 0.2) 45%, rgba(255, 255, 255, 0) 50%, rgba(255, 255, 255, 0.2) 55%, rgba(255, 255, 255, 0.2) 100%)'
      }
      style.transform += ` translate(${translateX}, ${translateY})`
      style['-webkit-transform'] += ` translate(${translateX}, ${translateY})`
      style['-moz-transform'] += ` translate(${translateX}, ${translateY})`
      style['-ms-transform'] += ` translate(${translateX}, ${translateY})`
      style['-o-transform'] += ` translate(${translateX}, ${translateY})`
      return style
    }
  },
  methods: {
    handleInput() {
      this.$nextTick(() => {
        const { width, height } = this.$refs.show.getBoundingClientRect()
        const { offsetWidth, offsetHeight } = this.$refs.showText
        if (width === 0 || height === 0 || offsetWidth === 0 || offsetHeight === 0) {
          return
        }
        const scaleX = width / offsetWidth
        const scaleY = height / offsetHeight
        const scale = Math.min(scaleX, scaleY)
        this.$refs.showText.style.transform += `scale(${scale})`
        this.$refs.showText.style['-webkit-transform'] += `scale(${scale})`
        this.$refs.showText.style['-moz-transform'] += `scale(${scale})`
        this.$refs.showText.style['-ms-transform'] += `scale(${scale})`
        this.$refs.showText.style['-o-transform'] += `scale(${scale})`
      })
    }
  }
}
</script>

代码中的 `watermarkStyle` 计算属性用于计算水印的样式，`handleInput` 方法用于在计算出水印样式后，将水印按照比例缩小并居中显示。注意，为了保证水印样式的正确性，需要在表单项加载完成之后计算水印样式，因此需要在 `handleInput` 方法中使用 `$nextTick` 方法等待表单项加载完成再进行计算。

要求：每次点击放大/缩小 2个像素字号，最大到32，最小到12 --> <div> <button class="jia">+</button> <button class="jian">-</button> </div>

可以为您提供以下代码来实现这个功能：

<div>
  <button class="jia">+</button>
  <button class="jian">-</button>
</div>

<script>
  const fontSizeElement = document.querySelector('body');
  let currentFontSize = 16; // 默认字体大小为16像素

  const jiaButton = document.querySelector('.jia');
  jiaButton.addEventListener('click', () => {
    if (currentFontSize < 32) {
      currentFontSize += 2;
      fontSizeElement.style.fontSize = `${currentFontSize}px`;
    }
  });

  const jianButton = document.querySelector('.jian');
  jianButton.addEventListener('click', () => {
    if (currentFontSize > 12) {
      currentFontSize -= 2;
      fontSizeElement.style.fontSize = `${currentFontSize}px`;
    }
  });
</script>

将上述代码放置在您的 HTML 文件中，它会为页面上的 "+" 和 "-" 按钮添加点击事件监听器。每次点击 "+" 按钮时，字体大小将增加2像素（最大到32像素）。每次点击 "-" 按钮时，字体大小将减少2像素（最小到12像素）。

请将代码复制到您的项目中，并根据需要进行调整。希望对您有帮助！