如何在使用axios和ReactJS进行反应选择后获取数据？

Question

I am newbie on ReactJS, I want to get a Price value just after the select of the Product name by react select and display it.

My method :

    constructor(props) {
        super(props);
        this.state = {
     PrixV: ""

     }
        PrixDisplay(selectprdt) {
            return axios.get("/app/getPrixprod/" + selectprdt).then(response => {
             if (response && response.data) {
                this.setState({
                  PrixV: response.data
                });
              }
console.log(response.data)
            }).catch(error => {
              console.error(error);
            });
          }

I try to read this value by :

<p>{this.state.PrixV} </p>

When I run it, nothing is displayd on the Price column and after I select the product name, I get :

Objects are not valid as a React child (found: object with keys {PrixV}). If you meant to render a collection of children, use an array instead.
    in p (at AjouterFacture.js:383)

And the console returns :

[{…}]0: {PrixV: "250.000"}length: 1__proto__: Array(0)

How can I read and display it ?

Answer 1

 constructor(props) {
          super(props);
          this.state = {
                mydata: ''
};

productNameSelected(selectprdt) {//not sure from where you will get selectprdt variable , but something like this will work
    axios.get("/app/getPrixprod/" + selectprdt).then(response => {
        if (response && response.data) {
          this.setState( {mydata : response.data});
      }
      console.log(response.data)
      })
  }

<p>{this.state.mydata} </p> //my data should not be a object , so you need to make string if you wnat to directly use it here

Edit

I can see you are able to get the response , but react still gives error:- change the paragrah code to

<p>{this.state.PrixV[0].PrixV} </p>

Or The good way will be to set the data properly so let paragrah be same

<p>{this.state.PrixV} </p>

PrixDisplay(selectprdt) {
    return axios.get("/app/getPrixprod/" + selectprdt).then(response => {
        if (response && response.data && response.data[0]) {
            this.setState({
            PrixV: response.data[0].PrixV
            });
        }
            console.log(response.data)
        }).catch(error => {
        console.error(error);
    });
}

You are getting the error because currently you are getting PrixV as an array(object) not a primitive data type. Hope this solves the issue.

Answer 2

You must use the map, try to change the code like this :

    constructor(props) {
        super(props);
        this.state = {
     Prix: []};
    render() {
    let {
          Prix
        } = this.state.Prix;
    return (
     <td>
 {  this.state.Prix.map((pr, k) => 
      <p key={k} >{pr.PrixV} </p>
                       )} 
                         </td>
    );}
    PrixDisplay(selectprdt) {
        return axios.get("/app/getPrixprod/" + selectprdt).then(response => {
         if (response && response.data) {
            this.setState({
              Prix: response.data
            });
          }

        }).catch(error => {
          console.error(error);

        });
      }

I hope that's will be helpful.