javascript - 在节点 jd 错误中出现此错误：TypeError: Cannot read property '0' of undefined

Question

嗨，我正在尝试使用 binance api 实现本地订单簿，但是我时不时地不断收到此错误，但它并不总是发生，但如果它确实会在早期发生，请帮助

这是运行从外部文件调用导出函数以处理来自消息的 Web 套接字的数据的主文件

wsClient.subscribeSpotDiffBookDepth("btcusdt");
wsClient.on('message', (data) => {

  // Setup and process order book information
  order_book.update_orderbook(data);
  if(order_book.ready === 1){
    order_book.get_orderbook_history();
  }

});

wsClient.on('error', err => {
  /* handle error */
    console.log("this is it 2 " + err);
});

wsClient.on('close', () => {
  /* ... */
});

外部文件中的导出函数

exports.update_orderbook = function(data) {
  if(data.e == "depthUpdate"){
    if(this.ready === 0){
      this.ready = 1;
      console.log("Stage 1 in play");
    }else{
      this.buffer += data;
    }

    if(this.ready === 2 && this.asks != null && this.bids != null){
      if(undefined !== this.asks && undefined !== this.bids && undefined !== data.a && undefined !== data.b){
        if(data.U <= this.lastUpdateId + 1 && data.u >= this.lastUpdateId + 1){

      // error is coming from calling this function-------------------------------------------------------
          var temp_array1 = sort_array(this.asks, data.a);
          var temp_array2 = sort_array(this.bids, data.b);
          this.asks = temp_array1;
          this.bids = temp_array2;
          this.lastUpdateId = data.u;

          console.log("Stage 3");
        }
      }
    }else{
      this.buffer += data;
    }
  }
}

排序和更新数组的函数

function sort_array(array1, array2){
  for(let x in array2){
    if(array2[x][1] == 0){
      for(let i in array2){
        if(array1[i][0] === array2[x][0]){
          array1.splice(i, 1);
        }
      }
    }else{
      var in_array = false;
      for(let i in array1){
        // this seems to be the problem area---------------------------------------------------------
        if(array1[i][0] === array2[x][0]){ 
          array1[i] = array2[x];
          in_array = true;
        }
      }
      if(!in_array){
        array1.push(array2[x]);
      }
    }
  }
  return array1;
}

错误日志