如何异步加载vuejs中的图像src url？ [英] How to load image src url in vuejs asyncronously?

问题描述

图片网址在控制台中打印但未呈现为src属性。如何在vuejs中使用async和await来实现这一点？

The image url is printing in console but not rendering to src attribute. How to achieve this with async and await in vuejs?

<div v-for="(data, key) in imgURL" :key="key">
   <img :src= "getLink(data)" />
</div>

其中imgURL包含文件名，它是文件名的集合。

Where imgURL contains file name and it is collections of file names.

  methods: {
     async getLink(url){
      let response = await PostsService.downloadURL({
        imgURL : url
      })
      console.log(response.data)
      return response.data
     }
  }

我从后端获取带有axios的URL。

I am getting URL from the backend with axios.

推荐答案

这是不可能的是，从值创建/更新DOM的过程是一个同步过程。因为Vue.js将直接使用 getLink 返回的值/对象，在您的情况下将是Promise对象。

That's not possible that way, the process of creating/updating the DOM from the values is a synchronous process. And because of that Vue.js would use the value/object returned by the getLink directly as is, which in your case would be a Promise object.

要解决此问题，您需要为这些图像创建自己的组件。在该组件的创建回调中，您将调用 getLink ，然后在 getLink 方法中设置数据<收到数据后立即code> link ，这将触发重新报名。

To solve the problem you would need to create an own component for those images. In the created callback of that component, you would call getLink, in the getLink method you then would set the data link as soon as the data is received, and that would trigger a rerender.

created() {
  // when the instance ist create call the method
  this.getLink();
},

methods: {
  async getLink(){
    let response = await PostsService.downloadURL({
      imgURL : this.url
    })
    console.log(response.data)
    this.link = response.data
  }
}

在图像组件的模板中，你会有这样的东西：

In the template of the image component you would have something like this:

<img :src= "link">

您确定现在可以扩展该图像组件以包含加载指示器或类似的东西。

You for sure can now extend that image component to include a loading indicator or something like that.

Vue.component('my-image-component', {
  props: {
    url: {type:String, required: true}
  },
  data : function() {
    return {link : 'loading'}
  },
  template: '<div>{{ link }} </div>',
  created() {
    this.getLink();
  },
  methods: {
    getLink() {
      setTimeout(() => {
        this.link = 'response url for link: ' + this.url
      }, 1000)
    }
  }
})


new Vue({
  el: '#app',
  data: {
    "imgURL": {
      test1: "1234",
      test2: "5678"
    }
  }
})

<div id="app">
  <div v-for="(data, key) in imgURL" :key="key">
    <my-image-component :url="data"></my-image-component>
  </div>
</div>


<script src="https://cdnjs.cloudflare.com/ajax/libs/vue/2.5.16/vue.min.js" type="text/javascript" charset="utf-8"></script>

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