Vue+el-upload上传文件，覆盖默认的上传行为，可以自定义上传的实现

<template>
  <div>
    <el-upload class="upload-demo" action size="mini" :file-list="fileListone" :http-request="uploadMehod">
      <el-button size="mini" type="primary" :loading="loadingOne">上传</el-button>
      <div slot="tip" class="el-upload__tip">注:单文件上传</div>
    </el-upload>
  </div>
</template>

<script>
export default {
  data: function() {
    return {
      loadingOne: false,
      fileListone: [],
    }
  },
  methods: {
    async uploadMehod(params) {
      this.loadingOne = true
      this.fileListone.unshift(params.file)
      let formData = new FormData()
      formData.append('file', params.file)
      let { data } = await setDelivery(formData) //axios
      if (data === 'success') {
        this.$message.success(data)
      } else {
        this.$message.error(data)
      }
      this.loadingOne = false
    },
  }
}
</script>
<style scoped lang="scss">
::v-deep input {
  width: 200px;
}
.el-upload__tip {
  color: red;
}
</style>