elment-ui上传组件，钩子函数（on-success 文件上传成功时的钩子）传递参数

开发需求：在已上传的图片列表中，点击图片实现上传替换

<template>
	<dz-upload
		list-type="picture-card"
		class="picture-item"
		:on-preview="handlePictureCardPreview"
		//通过es5的bind，绑定到函数上，就可以实现钩子函数的传参了
		:on-success="handleAvatarSuccess.bind(this,index)"
		:show-file-list="false"
		multiple
	>
		<img :src="imageUrl" width="100%" height="100%" />
	</dz-upload>
</template>

<script>
export default {
  data() {
    return {
      imageUrl: ''
    }
  },
  methods: {
  	//这里在前面接参
    handleAvatarSuccess(index,response,file,fileList){
      console.log(index)
    }
  }
}
</script>