二进制流转base64https://blog.csdn.net/m0_60067716/article/details/124606097

 核心代码

    // base64 转 二进制流(blob)
    dataURLtoBlob(dataurl) {
      var arr = dataurl.split(","),
        mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]),
        n = bstr.length,
        u8arr = new Uint8Array(n);
      while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new Blob([u8arr], {
        type: mime,
      });
    },

完整代码

<template>
  <div class="app">
    <img :src="imgSrc" alt="图片" />
  </div>
</template>
<script>
import axios from "axios";
export default {
  name: "app",
  data() {
    return {
      imgSrc: "",
    };
  },
  methods: {
    // 二进制流 转 base64
    getBase64(data) {
      return new Promise((resolve, reject) => {
        const blob = new Blob([data], { type: "image/jpg" }); //类型一定要写！！！
        const reader = new FileReader();
        reader.readAsDataURL(blob);
        reader.onload = () => resolve(reader.result);
        reader.onerror = (error) => reject(error);
      });
    },
    // base64 转 二进制流(blob)
    dataURLtoBlob(dataurl) {
      var arr = dataurl.split(","),
        mime = arr[0].match(/:(.*?);/)[1],
        bstr = atob(arr[1]),
        n = bstr.length,
        u8arr = new Uint8Array(n);
      while (n--) {
        u8arr[n] = bstr.charCodeAt(n);
      }
      return new Blob([u8arr], {
        type: mime,
      });
    },
  },
  mounted() {
    //网上随便找的图片
    const url =
      "https://img0.baidu.com/it/u=73689209,3130028231&fm=253&fmt=auto&app=138&f=JPEG";
    axios
      .get(url, {
        responseType: "blob", //一定要传！！！
      })
      .then((res) => {
        console.log(res.data, "二进制流");
        // 二进制流 转base64
        this.getBase64(res.data).then((binary) => {
          console.log(binary, "base64");
          // base64转 二进制流(blob)
          let blob = this.dataURLtoBlob(binary);
          console.log(blob, "blob");
          // 再转为file对象，放到页面上显示
          const objectURL = URL.createObjectURL(blob);
          console.log(objectURL, "objectURL");
          this.imgSrc = objectURL;
        });
      });
  },
};
</script>