My variable is undefined in my render method-CodePudding

I have a variable that I need in my React class.

But when I define it in the construtor, it becomes undefined when I try to use it in the render() method.

How can I make it so that my variable is available in the render() method?

Here is what I have:

export default class GameConsole extends React.PureComponent {

constructor(props) {
    super(props);

    var domainUrl = window.location.origin;
}

render() {
    return (
        <div>
            <GameControl
               init={{
                  masterUrl = domainUrl;

CodePudding user response：

Write this:

export default class GameConsole extends React.PureComponent {

constructor(props) {
    super(props);
        
}


render() {

var domainUrl = window.location.origin;
    return (
        <div>
            <GameControl
               init={{
                  masterUrl = domainUrl;

CodePudding user response：

Assign the value to the component's local state:

constructor() {
  super();
  this.state = {
    domainUrl: window.location.origin,
  };
}

render() {
  // Can access it on `this.state` inside render
  this.state.domainUrl;
}