真的没有办法从失败的 js 获取请求中获取响应主体吗？

Question

如果请求失败 (400)，新的 js 获取 API 会失败：

fetch(uri).catch(function(err) {
   console.log(err);
});

出现这种情况真的没有办法获取到response body吗？例如检查错误代码。

编辑：我创建了一个 js fiddle：https://jsfiddle.net/4x4xLwqo/ that calls this mockbin endpoint: http://mockbin.org/bin/d87acbb0-526e-4d66-aea4-b827d9c35031/view

编辑 2：更新 jsfiddle 以使用更好的端点：https://jsfiddle.net/4x4xLwqo/2/

Answer 1

如果遇到 HTTP 错误，

fetch 不会进入 catch。您可以使用常规 then.

来处理

来自MDN：

A fetch() promise will reject with a TypeError when a network error is encountered, although this usually means permission issues or similar — a 404 does not constitute a network error, for example. An accurate check for a successful fetch() would include checking that the promise resolved, then checking that the Response.ok property has a value of true.

以及来自 MDN 的附带示例：

fetch('flowers.jpg').then(function(response) {
  if(response.ok) {
    response.blob().then(function(myBlob) {
      var objectURL = URL.createObjectURL(myBlob);
      myImage.src = objectURL;
    });
  } else {
    console.log('Network response was not ok.');
  }
})
.catch(function(error) {
  console.log('There has been a problem with your fetch operation: ' + error.message);
});

真的没有办法从失败的 js 获取请求中获取响应主体吗？

Is there really no way to get the response body from a failed js fetch request?

javascript

fetch-api