React子组件的onChange事件更新状态 [英] onChange event for React child component to update state

问题描述

我正在尝试学习如何实现React表单（ES6语法）并将每个字段的onChange事件传递给负责更新状态的控制器父组件。这适用于标准的html元素，但我正在尝试预先制作的Datepicker（ https ：//www.npmjs.com/package/react-bootstrap-date-picker ）对于日期字段，并且不能以相同的方式将事件简单地传递回父级。有没有一种简单的方法来解决这个问题？

I'm trying to learn how to implement a React form (ES6 syntax) and pass the onChange events for each field up to a controller parent component which is responsible for updating the state. This works fine for standard html elements, however I am trying a pre-canned Datepicker (https://www.npmjs.com/package/react-bootstrap-date-picker) for a date field and can't readily pass the event back up to the parent in the same way. Is there a simple way to address this?

控制器组件

   class Parent extends React.Component {
    constructor (props) {
        super(props);
        this.state = {job: ''} 
    }

    setJobState(event) {
        var field = event.target.name;
        var value = event.target.value;
        this.state.job[field] = value;
        this.setState({job: this.state.job});
    }


    render () {
        return <Child onChange={this.setJobState.bind(this)} />
    }
}

子组件

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

    }

    render () {
        <form>
         <input type="text" name="jobNumber" onChange={this.props.onChange} /> 
         <DatePicker name="dateCmmenced" onChange={this.props.onChange}  />
        </form>
    }
}

推荐答案

使用标准浏览器调用 onChange DatePicker 的处理程序更改事件，但值和 formattedValue 作为参数。我建议在 Child 组件中注册不同的 onChange 处理程序，以转换相应的输入字段的事件：

The onChange handler for the DatePicker is not called with a standard browser change event, but with value and formattedValue as arguments. I would recommend to register different onChange handlers in your Child component that transform the respective input field's event:

控制器组件

class Parent extends React.Component {
    constructor (props) {
        super(props);
        this.state = {} 
    }

    onChange(field, value) {
        // parent class change handler is always called with field name and value
        this.setState({[field]: value});
    }


    render () {
        return <Child onChange={this.onChange.bind(this)} />
    }
}

子组件

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

    onFieldChange(event) {
        // for a regular input field, read field name and value from the event
        const fieldName = event.target.name;
        const fieldValue = event.target.value;
        this.props.onChange(fieldName, fieldValue);
    }

    onDateChange(dateValue) {
        // for a date field, the value is passed into the change handler
        this.props.onChange('dateCommenced', dateValue);
    }

    render () {
        return <form>
          <input type="text" name="jobNumber" onChange={this.onFieldChange.bind(this)} /> 
          <DatePicker onChange={this.onDateChange.bind(this)}  />
        </form>
    }
}

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