javascript - 状态更改时不必要地触发 Redux 操作

Question

我正在尝试将 socketCluster 与一个简单的 redux 应用集成。目前，只有一个功能可以获取组件中当前状态的值并通过中间件将其发送到服务器。

这是我的 actions.js 文件

export function signupRequest(creds){
  return{
    type: SIGNUP_REQUEST,
    isFetching: true,
    isAuthenticated: false,
    creds
  }
}

我的 reducer :

function signUp(state={
  isFetching:false,
  isAuthenticated: localStorage.getItem('id_token')? true : false
},action)
{
  switch(action.type){
    case SIGNUP_REQUEST:
      return Object.assign({},state,{
        isFetching:true,
        isAuthenticated: false,
        user: action.creds
      })
}

我有一个中间件功能，负责将输入发送到服务器

中间件.js

export default socket => store => next => action => {
  socket.emit('action',action);
}

我的客户端 index.js 文件

const socket = connect();
const createStoreWithMiddleware = applyMiddleware(middlewares(socket))(createStore);
const store = createStoreWithMiddleware(reducer);

let rootElement = document.getElementById('root')

render(
  <Provider store={store}>
    <App/>
  </Provider>,rootElement
)

我的 App.jsx 容器:

class App extends Component{

  render(){
      const {dispatch,isAuthenticated,errorMessage,isFetching} = this.props;
    return(
      <Signup
        onButtonClick = {this.props.signupRequest}/>
    )
  }
}

function mapStateToProps(state){
  const {isAuthenticated,errorMessage,isFetching} = state.signUp

  return {
    isAuthenticated,
    errorMessage,
    isFetching
  }
}

function mapDispatchToProps(dispatch){
  return bindActionCreators({signupRequest:signupRequest},dispatch)
}

export default connect(mapStateToProps,mapDispatchToProps)(App);

我的注册组件:

class Signup extends Component{

  constructor(props){
    super(props);

    this.state = {name:''};
    this.onInputChange = this.onInputChange.bind(this)
  }

  onInputChange(event){
    this.setState({name:event.target.value})
  }

  render(){
    return (
      <div>
        <input type="text"
          ref="username"
          className="SignupUsername"
          placeholder="Username"
          value = {this.state.name}
          onChange={this.onInputChange}
          />
        <button onClick= {this.props.onButtonClick(this.state.name)} >
          Signup
        </button>
      </div>
    )
  }
}

export default Signup

我面临的问题是中间件/操作在输入中被每次按键触发。我只想在按钮单击事件上调用中间件。

这是我在服务器端得到的输出

action recieved : { type: 'SIGNUP_REQUEST',
  isFetching: true,
  isAuthenticated: false,
  creds: 'a' }
action recieved : { type: 'SIGNUP_REQUEST',
  isFetching: true,
  isAuthenticated: false,
  creds: 'as' }
action recieved : { type: 'SIGNUP_REQUEST',
  isFetching: true,
  isAuthenticated: false,
  creds: 'asd' }
action recieved : { type: 'SIGNUP_REQUEST',
  isFetching: true,
  isAuthenticated: false,
  creds: 'asda' }
action recieved : { type: 'SIGNUP_REQUEST',
  isFetching: true,
  isAuthenticated: false,
  creds: 'asdas' }
action recieved : { type: 'SIGNUP_REQUEST',
  isFetching: true,
  isAuthenticated: false,
  creds: 'asdasd' }

如您所见，套接字在输入中的每个按键上发送操作。 点击按钮也不会调用中间件

编辑 - 我尝试将注册组件转换为容器 - 但我似乎仍然遇到同样的问题

class Signup extends Component{

  constructor(props){
    super(props);

    this.state = {name:''};
    this.onInputChange = this.onInputChange.bind(this)
  }

  onInputChange(event){
    this.setState({name:event.target.value})
  }

  render(){
    return (
      <div>
        <input type="text"
          ref="username"
          className="SignupUsername"
          placeholder="Username"
          value = {this.state.name}
          onChange={this.onInputChange}
          />
        <button onClick= {this.props.signupRequest(this.state.name)} >
          Signup
        </button>
      </div>
    )
  }
}

function mapDispatchToProps(dispatch){
  return bindActionCreators({signupRequest:signupRequest},dispatch)
}

export default connect(null,mapDispatchToProps)(Signup)

Answer 1

原来问题出在 onClick 事件上 - 我将 onClick 事件转换为如下函数:

<button onClick= {() => this.props.signupRequest(this.state.name)} >
  Signup
</button>

反对

  <button onClick= {this.props.signupRequest(this.state.name)} >
          Signup
        </button>