使用iView Upload 組件實現(xiàn)手動上傳圖片的示例代碼

更新時間：2018年10月01日 11:06:55 作者：與蟒唯舞

這篇文章主要介紹了使用iView Upload 組件實現(xiàn)手動上傳圖片的示例代碼，小編覺得挺不錯的，現(xiàn)在分享給大家，也給大家做個參考。一起跟隨小編過來看看吧

在過去，瀏覽器是不允許我們讀取本地的文件，包括圖片。因此，當我們需要預覽一個圖片的時候，往往先將它傳送到服務端，然后服務端返回一個訪問 url 地址，達到預覽圖片的功能。如今，隨著標準不斷的改善，JavaScript 里的 API 越來越多，我們可以通過直接讀取本地文件的方式來加載我們想要看到的文本或者圖片，一定程度上減少了服務端的壓力。

Upload 組件參考文檔：https://www.iviewui.com/components/upload

文檔提供的參考代碼：

<template>
  <div class="demo-upload-list" v-for="item in uploadList">
    <template v-if="item.status === 'finished'">
      ![](item.url)
      <div class="demo-upload-list-cover">
        <Icon type="ios-eye-outline" @click.native="handleView(item.name)"></Icon>
        <Icon type="ios-trash-outline" @click.native="handleRemove(item)"></Icon>
      </div>
    </template>
    <template v-else>
      <Progress v-if="item.showProgress" :percent="item.percentage" hide-info></Progress>
    </template>
  </div>
  <Upload
    ref="upload"
    :show-upload-list="false"
    :default-file-list="defaultList"
    :on-success="handleSuccess"
    :format="['jpg','jpeg','png']"
    :max-size="2048"
    :on-format-error="handleFormatError"
    :on-exceeded-size="handleMaxSize"
    :before-upload="handleBeforeUpload"
    multiple
    type="drag"
    action="http://jsonplaceholder.typicode.com/posts/"
    style="display: inline-block;width:58px;">
    <div style="width: 58px;height:58px;line-height: 58px;">
      <Icon type="camera" size="20"></Icon>
    </div>
  </Upload>
  <Modal title="查看圖片" v-model="visible">
    ![]('https://o5wwk8baw.qnssl.com/' + imgName + '/large')
  </Modal>
</template>
<script>
  export default {
    data () {
      return {
        defaultList: [
          {
            'name': 'a42bdcc1178e62b4694c830f028db5c0',
            'url': 'https://o5wwk8baw.qnssl.com/a42bdcc1178e62b4694c830f028db5c0/avatar'
          },
          {
            'name': 'bc7521e033abdd1e92222d733590f104',
            'url': 'https://o5wwk8baw.qnssl.com/bc7521e033abdd1e92222d733590f104/avatar'
          }
        ],
        imgName: '',
        visible: false,
        uploadList: []
      }
    },
    methods: {
      handleView (name) {
        this.imgName = name;
        this.visible = true;
      },
      handleRemove (file) {
        // 從 upload 實例刪除數(shù)據(jù)
        const fileList = this.$refs.upload.fileList;
        this.$refs.upload.fileList.splice(fileList.indexOf(file), 1);
      },
      handleSuccess (res, file) {
        // 因為上傳過程為實例，這里模擬添加 url
        file.url = 'https://o5wwk8baw.qnssl.com/7eb99afb9d5f317c912f08b5212fd69a/avatar';
        file.name = '7eb99afb9d5f317c912f08b5212fd69a';
      },
      handleFormatError (file) {
        this.$Notice.warning({
          title: '文件格式不正確',
          desc: '文件 ' + file.name + ' 格式不正確，請上傳 jpg 或 png 格式的圖片。'
        });
      },
      handleMaxSize (file) {
        this.$Notice.warning({
          title: '超出文件大小限制',
          desc: '文件 ' + file.name + ' 太大，不能超過 2M。'
        });
      },
      handleBeforeUpload () {
        const check = this.uploadList.length < 5;
        if (!check) {
          this.$Notice.warning({
            title: '最多只能上傳 5 張圖片。'
          });
        }
        return check;
      }
    },
    mounted () {
      this.uploadList = this.$refs.upload.fileList;
    }
  }
</script>
<style>
  .demo-upload-list{
    display: inline-block;
    width: 60px;
    height: 60px;
    text-align: center;
    line-height: 60px;
    border: 1px solid transparent;
    border-radius: 4px;
    overflow: hidden;
    background: #fff;
    position: relative;
    box-shadow: 0 1px 1px rgba(0,0,0,.2);
    margin-right: 4px;
  }
  .demo-upload-list img{
    width: 100%;
    height: 100%;
  }
  .demo-upload-list-cover{
    display: none;
    position: absolute;
    top: 0;
    bottom: 0;
    left: 0;
    right: 0;
    background: rgba(0,0,0,.6);
  }
  .demo-upload-list:hover .demo-upload-list-cover{
    display: block;
  }
  .demo-upload-list-cover i{
    color: #fff;
    font-size: 20px;
    cursor: pointer;
    margin: 0 2px;
  }
</style>

自己實現(xiàn)手動上傳：

<template>
  <div>
    <div class="demo-upload-list" v-for="item in uploadList">
      ![](item.url)
      <div class="demo-upload-list-cover">
        <Icon type="ios-trash-outline" @click.native="handleRemove(item)"></Icon>
      </div>
    </div>
    <Upload ref="upload" :show-upload-list="false" :format="['jpg','jpeg','png']" :max-size="2048" :before-upload="handleBeforeUpload" :on-format-error="handleFormatError" :on-exceeded-size="handleMaxSize" type="drag" action="http://jsonplaceholder.typicode.com/posts/" style="display: inline-block;width:58px;">
      <div style="width: 58px;height:58px;line-height: 58px;">
        <Icon type="camera" size="20"></Icon>
      </div>
    </Upload>
  </div>
</template>
<script>
export default {
 methods: {
  data(){
    return {
      uploadList: []
    }
  },
  handleBeforeUpload(file) {
    // 創(chuàng)建一個 FileReader 對象
    let reader = new FileReader()
    // readAsDataURL 方法用于讀取指定 Blob 或 File 的內容
    // 當讀操作完成，readyState 變?yōu)?DONE，loadend 被觸發(fā)，此時 result 屬性包含數(shù)據(jù)：URL（以 base64 編碼的字符串表示文件的數(shù)據(jù)）
    // 讀取文件作為 URL 可訪問地址
    reader.readAsDataURL(file)

    const _this = this
    reader.onloadend = function (e) {
      file.url = reader.result
      _this.uploadList.push(file)
    }
  },
  handleRemove(file) {
    this.uploadList.splice(this.uploadList.indexOf(file), 1)
  },
  handleFormatError(file) {
   this.$Notice.warning({
    title: '文件格式不正確',
    desc: '文件 ' + file.name + ' 格式不正確，請上傳 jpg 或 png 格式的圖片。'
   })
  },
  handleMaxSize(file) {
   this.$Notice.warning({
    title: '超出文件大小限制',
    desc: '文件 ' + file.name + ' 太大，不能超過 2M。'
   })
  }
 }
}
</script>
<style scoped>
.demo-upload-list {
  display: inline-block;
  width: 60px;
  height: 60px;
  text-align: center;
  line-height: 60px;
  border: 1px solid transparent;
  border-radius: 4px;
  overflow: hidden;
  background: #fff;
  position: relative;
  box-shadow: 0 1px 1px rgba(0, 0, 0, .2);
  margin-right: 4px;
}

.demo-upload-list img {
  width: 100%;
  height: 100%;
}

.demo-upload-list-cover {
  display: none;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 0;
  right: 0;
  background: rgba(0, 0, 0, .6);
}

.demo-upload-list:hover .demo-upload-list-cover {
  display: block;
}

.demo-upload-list-cover i {
  color: #fff;
  font-size: 20px;
  cursor: pointer;
  margin: 0 2px;
}

.ivu-icon {
  line-height: 58px;
}
</style>

以上就是本文的全部內容，希望對大家的學習有所幫助，也希望大家多多支持腳本之家。

您可能感興趣的文章: