setState return NULL in React and Node Js

Question

I have a Node Js API where I get my database data with a find function. It works perfectly and send my results. Using React and Axios, I get the data but as soon as I pass the data into setState it sends null.

Here is my API find() function

dbo.collection("students").find({}).toArray(function(err, result) {
        if (err) throw err;
        var students = result;
        reponse.send(students);
        db.close();
    });

And here is my Axios constructor() and componentDidMont()

    constructor() {
    super();
    this.state = {
      students: [],
    }
  }

    componentDidMount() {
    axios.get("http://localhost:3333/").then((data) => {
      console.log(data);
      this.setState({students:data.data.students});
      console.log(this.state);
    });
  }

console.log(data) return this

`Object { data: (33) […], status: 200, statusText: "OK", headers: {…}, config: {…}, request: XMLHttpRequest }`

While console.log(this.state) return this

Object { students: undefined }

Are you sure there is a `students` in your `data.data`? – tkausl May 07 '20 at 17:04 — tkausl, May 07 '20 at 17:04

score 0 · Answer 1 · answered May 07 '20 at 17:15

0

Firstly state updates are async so you wouldn't see the updated state immediately

Secondly, the response data has data which is an array, so you just need to set the state with data.data

this.setState({students:data.data});

answered May 07 '20 at 17:15

Shubham Khatri

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setState return NULL in React and Node Js

1 Answers1