javascript 类型错误：data.filter 不是函数
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TypeError: data.filter is not a function
提问by shaz
I am trying to filter an arrayof JSONobjects, which I get from an APIcall on my proxy. I am using a Node.jsweb framework Expressto make the APIcall.
我试图来过滤array的JSON对象，这是我从一个拿到API我的电话proxy。我正在使用Node.jsWeb 框架Express进行API调用。
API returns the following:
API 返回以下内容：
{
data: [
{
type: "aaa",
name: "Cycle",
id: "c949up9c",
category: ["A","B"]
},
{
type: "bbb",
name: "mobile",
id: "c2rt4Jtu",
category: ["C","D"]
},
...
]
}
server.js
服务器.js
function sortDataByID(data) {
return data.filter(function(item) {
return item.id == 'c949up9c';
});
}
app.get('/products', (req, res) => {
const options = {
url: BASE_URL + '/products',
headers: {
'Authorization': 'hgjhgjh',
'Accept': 'application/json'
}
}
request.get(options).pipe(sortDataByID(res));
});
I keep getting the following error message.
我不断收到以下错误消息。
TypeError: data.filter is not a function
类型错误：data.filter 不是函数
What is the obvious mistake here? Anyone?
这里明显的错误是什么？任何人？
采纳答案by Sello Mkantjwa
I've personally never seen piping to a function. I don't think that should work. In any case:
我个人从未见过管道到函数。我不认为那应该奏效。任何状况之下：
You can use a callback instead of piping. Try this:
您可以使用回调而不是管道。试试这个：
app.get('/products', (req, res) => {
const options = {
url: BASE_URL + '/products',
json: true, //little convenience flag to set the requisite JSON headers
headers: {
'Authorization': 'hgjhgjh',
'Accept': 'application/json'
}
}
request.get(options, sortDataByID);
});
});
function sortDataByID(err, response, data){ //the callback must take 3 parameters
if(err){
return res.json(err); //make sure there was no error
}
if(response.statusCode < 200 || response.statusCode > 299) { //Check for a non-error status code
return res.status(400).json(err)
}
let dataToReturn = data.data.filter(function(item) { //data.data because you need to access the data property on the response body.
return item.id == 'c949up9c';
}
res.json(dataToReturn);
}
回答by Adrien De Peretti
I think your mistake is to think than resis the datathan you expect.
我认为你的错误是认为比res是data比您预期。
But if you take a look inside resyou should find the data.
但是如果你看看里面，res你应该会发现data.
so you must get datafrom the resand use it.
所以你必须得data从res并使用它。
For example:
例如：
const data = res.data;
request.get(options).pipe(sortDataByID(data))
Have a nice day !
祝你今天过得愉快 ！
