Error Uncaught TypeError Cannot read property setState of undefined

0 votes

I am getting the following error

Uncaught TypeError: Cannot read property 'setState' of undefined

even after binding delta in the constructor.

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

        this.state = {
            count : 1
        };

        this.delta.bind(this);
    }

    delta() {
        this.setState({
            count : this.state.count++
        });
    }

    render() {
        return (
            <div>
                <h1>{this.state.count}</h1>
                <button onClick={this.delta}>+</button>
            </div>
        );
    }
}
Jun 4, 2020 in Angular by kartik
• 37,510 points
1,036 views

1 answer to this question.

0 votes

Hello @kartik,

This is due to this.delta not being bound to this.

In order to bind set this.delta = this.delta.bind(this) in the constructor:

constructor(props) {
    super(props);

    this.state = {
        count : 1
    };

    this.delta = this.delta.bind(this);
}

Currently, you are calling bind. But bind returns a bound function. You need to set the function to its bound value.

Thank You!!

answered Jun 4, 2020 by Niroj
• 82,880 points

Related Questions In Angular

0 votes
1 answer

Error: Cannot find module 'webpack/lib/node/NodeTemplatePlugin'

Hii kartik, Removing the node_modules and the package-lock.json ...READ MORE

answered Apr 22, 2020 in Angular by Niroj
• 82,880 points
15,257 views
0 votes
1 answer

Error:setState doesn't update the state immediately

Hello @kartik, The method setState() takes a callback. And ...READ MORE

answered Jun 4, 2020 in Angular by Niroj
• 82,880 points
4,854 views
0 votes
1 answer

What are the type of $watch()?

hey kartik, Before you move in to the ...READ MORE

answered Feb 3, 2020 in Angular by Niroj
• 82,880 points
600 views
0 votes
1 answer

What is the use of $eval in alert()?

Hey, kartik!! There is not much difference in ...READ MORE

answered Feb 4, 2020 in Angular by Niroj
• 82,880 points
970 views
0 votes
1 answer

What are the vulnerability related to PHP Form?

Hii, The $_SERVER["PHP_SELF"] variable can be used by ...READ MORE

answered Feb 13, 2020 in PHP by Niroj
• 82,880 points
2,691 views
+1 vote
1 answer

How can we send message multiple time to a specific person or group in whatsapp using loop?

Hii @kartik,  This is simple task to send single ...READ MORE

answered Feb 28, 2020 in Java-Script by Niroj
• 82,880 points
17,310 views
0 votes
1 answer

What is meant by passing the variable by value and reference in PHP?

Hello, When the variable is passed as value ...READ MORE

answered Mar 27, 2020 in PHP by Niroj
• 82,880 points
2,913 views
0 votes
1 answer

Connection with MySQL server using PHP. How can we do that?

Hey @kartik, You have to provide MySQL hostname, ...READ MORE

answered Mar 27, 2020 in PHP by Niroj
• 82,880 points
956 views
0 votes
1 answer

Error: Cannot read property 'setState' of undefined

Hello @kartik, This is due to this.delta not being bound ...READ MORE

answered Jul 22, 2020 in Angular by Niroj
• 82,880 points
3,061 views
0 votes
1 answer

Error:Cannot read property 'remove' of undefined at BrowserDomAdapter.removeClass

Hello @kartik, There are several ways to add ...READ MORE

answered Sep 8, 2020 in Angular by Niroj
• 82,880 points
3,118 views
webinar REGISTER FOR FREE WEBINAR X
REGISTER NOW
webinar_success Thank you for registering Join Edureka Meetup community for 100+ Free Webinars each month JOIN MEETUP GROUP