我的问题是下一个:
//express server
app.post('/register', (req, res) => {
const {
password,
passwordConfirm
} = req.body;
if (password === passwordConfirm) {
//...
} else {
res.status(400).json("Passwords aren't matching")
}
})
//react function
onSubmitSignIn = () => {
const { password, passwordConfirm } = this.state;
let data = new FormData();
data.append('password', password);
data.append('passwordConfirm', passwordConfirm);
fetch('http://localhost:3001/register', {
method: 'post',
body: data
})
.then(response => response.json())
.then(user => {
//logs error message here
console.log(user)
})
//but I want to catch it here, and set the message to the state
.catch(alert => this.setState({alert}))
}
当我发送状态代码并将来自express的消息作为响应时,前端显然将其识别为响应,这就是为什么它将消息以“用户”身份记录到控制台的原因。但是如何发送到catch函数的错误呢?
最佳答案
如果fetch
出于某种原因无法解释API,则实际上只会出错。换句话说,它将因网络错误而出错。非2XX
状态代码不会显式错误。
您需要按照此处所述检查ok
属性:
-
fetch('http://localhost:3001/register', {
method: 'post',
body: data
})
.then(response => {
if (!response.ok) {
throw new Error('my api returned an error')
}
return response.json()
})
.then(user => {
console.log(user)
})
.catch(alert => this.setState({alert}))
关于javascript - 如何通过expressjs的响应在前端捕获错误?,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/53022281/