javascript - React js中的复选框不会改变

Question

我的主要组成部分如下:

export default class RegistrationFormStepFour extends React.Component{
constructor(props){
    super(props);
    this.state = {
        terms: false,
        emailNotifications: false,
        smsNotifications: false,
        errors: {}
    }
}


handleTerms(event){
    event.preventDefault();
    this.setState({terms: !this.state.terms});
}

render(){
    const language = this.props.currentLanguage;

    return (
        <div>
            <Terms
                nameYes="chcTerms"
                text={language.termsText}
                state={this.state.terms}
                onChange={this.handleTerms.bind(this)}
                currentLanguage={language}
                error={this.state.errors.terms}/>

        </div>
    );
}
}

组件术语如下:

import React from 'react';

const Terms = ({nameYes, text, state, onChange, error}) => {

let hasError = error ? "hasError" : "";

return (
    <div className="col-lg-12 text-center" style={{marginBottom: 30}}>
        <form>
            <label className="radio-inline">
                <input
                    type="checkbox"
                    name={nameYes}
                    checked={state}
                    onChange={onChange}
                    value=""/>
            </label>
        </form>
        <p className={`questionsText ${hasError}`} style={{marginTop: 10}}>{text}</p>
    </div>
);
};

export default Terms;

但是当我点击复选框时，没有任何反应。如果我在 terms 组件中控制台记录 state，它会显示正确的值。第一次是 false，当我单击复选框时不是 true，但未选中该复选框。

有什么建议吗？

Answer 1

event.preventDefault() 导致受控组件复选框出现问题。

http://www.matthiaslienau.de/blog/tags/checkbox

Checkboxes (and Radio Buttons): Manually updating state fails for checkboxes (and without having tested it: I think for radio controls as well). Why? The problem one will face is that the checkbox onChange event behaves in a special way since the era of HTML (how could I forget!): You may not toggle the state of a checkbox manually via the .checked property. Nor does React. The onChange (onClick) event is fired after the element state changed internally. This may just be reverted based on the return value of the event handler. See this post for a comprehensive examination of this fact.

const Terms = ({ nameYes, text, state, onChange, error }) => {
  let hasError = error ? "hasError" : "";
  return (
    <div>
      <form>
        <label className="radio-inline">
          <input
            type="checkbox"
            name={nameYes}
            checked={state}
            onChange={onChange} 
          />
        </label>
      </form>
      <p className={`questionsText ${hasError}`}>{text}</p>
    </div>
  );
};

class RegistrationFormStepFour extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      terms: false,
      emailNotifications: false,
      smsNotifications: false,
      errors: {}
    }
  }

  handleTerms(event) {
    this.setState({ terms: event.target.checked });
  }

  render() {
    const language = { termsText: 'Some Language' };
    return (
      <div>
        <Terms
          nameYes="chcTerms"
          text={language.termsText}
          state={this.state.terms}
          onChange={this.handleTerms.bind(this)}
          currentLanguage={language}
          error={this.state.errors.terms}/>
       {JSON.stringify(this.state)}
      </div>
    );
  }
}

ReactDOM.render(<RegistrationFormStepFour />, document.getElementById('app'))

<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/react/15.1.0/react-dom.min.js"></script>
<div id="app"></div>