javascript 类型错误：无法获取
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TypeError: Failed to fetch
提问by Mikael Nazaretyan
I have a index.pug file, that is render by GET, and Post that returns data into json.
我有一个由 GET 渲染的 index.pug 文件，以及将数据返回到 json 中的 Post。
router.get('/', function(req, res, next) {
res.render('index', { title: 'agrotaxi' });
});
router.post('/', async function(req, res) {
......
res.json(info);
});
The problem is that when you try to fetch the result i've got:
问题是，当您尝试获取结果时，我得到了：
Uncaught (in promise) TypeError: Failed to fetch
my fetch function:
我的提取功能：
document.getElementById('go').addEventListener('click',getdata);
function getdata() {
let start = document.getElementById('start').value;
let end = document.getElementById('end').value;
let options = {
"start": start,
"end": end
};
fetch('http://localhost:3000', {
method: 'post',
headers: {
"Content-type": "application/json; charset=UTF-8"
},
body:JSON.stringify(options)
})
.then(function(res){
return res.json(); //error here
})
.then(function(data){
console.log(data);
});
}
Don't understand what i do wrong. the pic of error
不明白我做错了什么。 错误的图片
回答by Jose Mato
Maybe the problem the fetch fails for some reason and you are not capturing the error, so, try adding the catch method in this way:
可能是由于某种原因获取失败的问题，而您没有捕获错误，因此，尝试以这种方式添加 catch 方法：
fetch('http://localhost:3000', {
method: 'post',
headers: {
"Content-type": "application/json; charset=UTF-8"
},
body:JSON.stringify(options)
}).then(function(res){
return res.json(); //error here
}).then(function(data){
console.log(data);
}).catch((error) => {
console.log(error);
});
