这是最简单的方法

const formValidator = (form) => {
    let returnData = {}
    console.log(form.length);

    for (let i = 0; i < form.length; i++) {
        const data = form[i]
        if (data.name != null && data.name != "") {
            returnData[data.name] = data.value;
        }
    }
    return returnData
}

在形式上

<form onSubmit={(e) => {
          e.preventDefault()
          let data = formValidator(e.currentTarget)
         }}>
          <RoundTextFiled name='app-id' style={{ marginTop: '10px', borderRadius: '20px' }} label="App id" fullWidth required />
          <RoundTextFiled name='api-hash' style={{ marginTop: '5px' }} label="Api hash" fullWidth required />
          <RoundTextFiled name='channel-id' style={{ marginTop: '5px' }} label="Channel id" fullWidth required />
          <Button type='submit' variant="contained" fullWidth style={{ padding: '10px', marginTop: '5px', borderRadius: '10px' }}>Login</Button>
        </form>

有几种方法可以做到这一点:

1)通过索引从数组的表单元素中获取值

handleSubmit = (event) => {
  event.preventDefault();
  console.log(event.target[0].value)
}

2)在html中使用name属性

handleSubmit = (event) => {
  event.preventDefault();
  console.log(event.target.elements.username.value) // from elements property
  console.log(event.target.username.value)          // or directly
}

<input type="text" name="username"/>

3)使用裁判

handleSubmit = (event) => {
  console.log(this.inputNode.value)
}

<input type="text" name="username" ref={node => (this.inputNode = node)}/>

完整的示例

class NameForm extends React.Component {
  handleSubmit = (event) => {
    event.preventDefault()
    console.log(event.target[0].value)
    console.log(event.target.elements.username.value)
    console.log(event.target.username.value)
    console.log(this.inputNode.value)
  }
  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        <label>
          Name:
          <input
            type="text"
            name="username"
            ref={node => (this.inputNode = node)}
          />
        </label>
        <button type="submit">Submit</button>
      </form>
    )
  }
}

我建议采取以下方法:

import {Autobind} from 'es-decorators';

export class Form extends Component {

    @Autobind
    handleChange(e) {
        this.setState({[e.target.name]: e.target.value});
    }

    @Autobind
    add(e) {
        e.preventDefault();
        this.collection.add(this.state);
        this.refs.form.reset();
    }

    shouldComponentUpdate() {
        return false;
    }

    render() {
        return (
            <form onSubmit={this.add} ref="form">
                <input type="text" name="desination" onChange={this.handleChange}/>
                <input type="date" name="startDate" onChange={this.handleChange}/>
                <input type="date" name="endDate" onChange={this.handleChange}/>
                <textarea name="description" onChange={this.handleChange}/>
                <button type="submit">Add</button>
            </form>
        )
    }

}

另一种方法是使用ref属性并使用this.refs引用值。这里有一个简单的例子:

render: function() {
    return (<form onSubmit={this.submitForm}>
        <input ref="theInput" />
    </form>);
},
submitForm: function(e) {
    e.preventDefault();
    alert(React.findDOMNode(this.refs.theInput).value);
}

更多信息可以在React文档中找到: https://facebook.github.io/react/docs/more-about-refs.html#the-ref-string-attribute

关于如何在React中使用单选按钮中描述的很多原因?这种方法并不总是最好的，但在一些简单的情况下确实是一种有用的替代方法。

如果你在项目中使用Redux，你可以考虑使用这个更高阶的组件https://github.com/erikras/redux-form。

从react中导入{useState}

导出默认函数App() { const [data, setData] = useState({})

const updateData = e => {
    setData({
        ...data,
        [e.target.name]: e.target.value
    })
}

const submit = e => {
    e.preventDefault()
    console.log(data)
}

return (
    <form onSubmit={submit}>
        <input
            name="email"
            type="email"
            onChange={updateData}
        />
        <input
            name="password"
            type="password"
            onChange={updateData}
         />
        <button>Submit</button>
    </form>
)

}