When Response.text() promise will reject?

Question

我看到在MDN/Response/text文档中显示了仅使用.text()和then的示例

response.text().then(function (text) {
// do something with the text response
});

它返回一个promise，用String解析。

由于lint规则，我需要把

// eslint-disable-next-line @typescript-eslint/no-floating-promises
res.text().then(async (t) => {

当我需要从Response.text()捕获被拒绝的承诺时，是否有用例?也许可以举一些例子?

Answer 1

如果响应已经是consumed/read，那么它可以失败/拒绝，也就是说，如果已经调用了。text/。

查看polyfill实现(https://github.com/github/fetch/blob/d1d09fb8039b4b8c7f2f5d6c844ea72d8a3cefe6/fetch.js#L301)，我没有看到其他可能的情况。

---

例子:

response.text()
.then(t1 => {
console.log({ t1 }); // after calling text() we can see the result here
return response; // but we decided to return the response to the next handler
})
.then(res =>res.text()) // here we try to read text() again
.then(t2 => console.log({ t2 })) // and expecting text to be logged here
.catch(er => console.log({ er })); // but the text() promise rejects with 
// TypeError: Failed to execute 'text' on 'Response': body stream already read