从流中获取的数据格式如下

小程序调用SSE接口

const requestTask = wx.request({
      url: `xxx`, // 需要请求的接口地址
      enableChunked: true, // enableChunked必须为true
      method: "GET",
      timeout: '120000',
      success(res) {
        console.log(res.data)
      },
      fail: function (error) {
        // 请求失败的操作
        console.error(error);
      },
      complete: function () {
        // 请求完成的操作，无论成功或失败都会执行
        console.log('请求完成', str);
      }
    })
    // 监听服务端返回的数据
    requestTask.onChunkReceived(res => {
      console.log( res, res.data);
    })

我这边接收到的数据类型为Uint8Array，需要处理成text文本（如上图）

 // 监听服务端返回的数据
    requestTask.onChunkReceived(res => {
      console.log( res, res.data);
      // Uint8Array转为text格式
      let arrayBuffer = res.data;
      let decoder = new TextDecoder('utf-8');
      let text = decoder.decode(arrayBuffer);
      //正则匹配上所有event:data后面的文字
      const eventRegex = /event:data\ndata:"data:(.*?)"/g;
      const eventRegexErr = /event:600\ndata:"(.*?)"/g;
      let matches = [];
      let match;
      if (text.indexOf('600') != -1) {//如果获取响应失败
        while ((match = eventRegexErr.exec(text)) !== null) {
          wx.showToast({
            title: match[1],
          })
          matches.push(match[1]);
        }
        str = str + matches.join('')
      } else {//如果获取响应成功
        while ((match = eventRegex.exec(text)) !== null) {
          matches.push(match[1]);
        }
        //处理成字符串
        str = str + matches.join('')
        console.log(text, str);
      }
    })

使对话有打字机效果

参考自：小程序实现 ChatGPT 聊天打字兼自动滚动效果

that.handleRequestResolve(str)
handleRequestResolve(result) {
    const timestamp = Date.now();
    const index = this.data.messageList.length
    const newMessageList = `messageList[${index}]`
    const contentCharArr = result.trim().split("")
    const content_key = `messageList[${index}].content`
    const finished_key = `messageList[${index}].finished`
    this.setData({
      thinking: false,
      [newMessageList]: {
        id: timestamp,
        finished: false
      }
    })
    currentContent = ''
    this.showText(0, content_key, finished_key, contentCharArr);
  },
  showText(key = 0, content_key, finished_key, value) {
    /* 所有内容展示完成 */
    if (key >= value.length) {
      this.setData({
        loading: false,
        [finished_key]: true
      })
      // wx.vibrateShort()
      return;
    }
    currentContent = currentContent + value[key]
    /* 渲染回话内容 */
    this.setData({
      [content_key]: currentContent,
    })
    setTimeout(() => {
      /* 递归渲染内容 */
      this.showText(key + 1, content_key, finished_key, value);
    }, 50);
  },

完整代码

 getDataStream(data) {
    let str = ''
    let that = this
    // 基础库为2.33.0
    const requestTask = wx.request({
      enableChunked: true, // 开启分片模式
      url: 'xxx', // 需要请求的接口地址
      enableChunked: true, // enableChunked必须为true
      method: "GET",
      responseType: "arraybuffer",
      timeout: '120000',
      success(res) {
        console.log(res.data)
      },
      fail: function (error) {
        // 请求失败的操作
        console.error(error);
      },
      complete: function () {
        // 请求完成的操作，无论成功或失败都会执行
        console.log('请求完成', str);
      }
    })
    // 监听服务端返回的数据
    requestTask.onChunkReceived(res => {
      console.log(res, res.data);
      // Uint8Array转为text格式
      let arrayBuffer = res.data;
      let decoder = new TextDecoder('utf-8');
      let text = decoder.decode(arrayBuffer);
      //正则匹配上所有event:data后面的文字
      const eventRegex = /event:data\ndata:"data:(.*?)"/g;
      const eventRegexErr = /event:600\ndata:"(.*?)"/g;
      let matches = [];
      let match;
      if (text.indexOf('600') != -1) { //如果获取响应失败
        while ((match = eventRegexErr.exec(text)) !== null) {
          wx.showToast({
            title: match[1],
          })
          matches.push(match[1]);
        }
        str = str + matches.join('')
      } else { //如果获取响应成功
        while ((match = eventRegex.exec(text)) !== null) {
          matches.push(match[1]);
        }
        //处理成字符串
        str = str + matches.join('')
        console.log(text, str);
      }
      that.handleRequestResolve(str)

    })
    requestTask.offChunkReceived(res => {
      console.log('事件完成状态');
    })
  },
  handleRequestResolve(result) {
    const timestamp = Date.now();
    const index = this.data.messageList.length
    const newMessageList = `messageList[${index}]`
    const contentCharArr = result.trim().split("")
    const content_key = `messageList[${index}].content`
    const finished_key = `messageList[${index}].finished`
    this.setData({
      thinking: false,
      [newMessageList]: {
        id: timestamp,
        finished: false
      }
    })
    currentContent = ''
    this.showText(0, content_key, finished_key, contentCharArr);
  },
  showText(key = 0, content_key, finished_key, value) {
    /* 所有内容展示完成 */
    if (key >= value.length) {
      this.setData({
        loading: false,
        [finished_key]: true
      })
      // wx.vibrateShort()
      return;
    }
    currentContent = currentContent + value[key]
    /* 渲染回话内容 */
    this.setData({
      [content_key]: currentContent,
    })
    setTimeout(() => {
      /* 递归渲染内容 */
      this.showText(key + 1, content_key, finished_key, value);
    }, 50);
  },