How to set the next state values based on previous values in React?-CodePudding

Here is an example:

class MyComp extends React.Component {
  constructor(props) {
    super(props);

    this.state = {
      firstName: 'xyz',
      lastName: 'abc';
      fullName: firstName   lastName
    };
  }

Trying the above technique gives me errors. I also tried using this.firstName and this.lastName but that also resulted in errors. How should I proceed?

Thanks.

CodePudding user response：

you should use this.state.firstname.....

because you use state in constructor and if you want to access that item you have to define this.state.'your item name'

class MyComp extends React.Component {

constructor(props) { super(props);

const firstName = 'xyz';
const lastName = 'abc';

this.state = {
  firstName,
  lastName,
  fullName: firstName   lastName
};

}

on this you can use this.state.firstname

CodePudding user response：

You can try as below

class MyComp extends React.Component {
  constructor(props) {
    super(props);
    
    const firstName = 'xyz';
    const lastName = 'abc';
    
    this.state = {
      firstName,
      lastName,
      fullName: firstName   lastName
    };
  }