javascript - 在 React、JavaScript 中捕获 504(网关超时)错误

Question

我有一个有效的 API 可以从服务器获取项目，如下所示。我正在使用 React 来使用这些数据。现在，我想捕获所有以 5__ 开头的服务器错误，并显示一条消息，如“未连接到互联网”或类似内容。

 export const GetItems = (operand, searchValue) => {
      const trimmedValue = searchValue.trim();
      let combinedResults;
      // make 2 API calls to search on both item_name and code;
      // then combine them;
      // there is no API method to do this, that I could find
      return getItemsByName(operand, trimmedValue)
      .then(result => (
        (combinedResults = [].concat(result))
      ))
      .then(() => getItemsByCode(operand, trimmedValue))
      .then(result => (
        (combinedResults = combinedResults.concat(result))
      ));
    };

目前，我需要查看控制台来检查连接是否有问题。

---

根据@Dane 的要求更新

const getItemsByCode = (operand, searchValue) => (
  FetchToJson(BuildCodeSearchUrl(operand, searchValue))
);

它只是调用一个方法来构建 URL。您可以认为一切正常，如果有连接就会得到响应。

Answer 1

使用catch():

return getItemsByName(operand, trimmedValue)
      .then(result => (
        (combinedResults = [].concat(result))
      ))
      .then(() => getItemsByCode(operand, trimmedValue))
      .then(result => (
        (combinedResults = combinedResults.concat(result))
      ))
      .catch((error) => {
        if (error.response) { // if there is response, it means its not a 50x, but 4xx

        } else {   // gets activated on 50x errors, since no response from server
          // do whatever you want here :)
        }            
      });