你可以将按钮上的onClick事件处理程序切换到表单上的onSubmit处理程序:

render : function() {
      return (
        <form onSubmit={this.handleLogin}>
          <input type="text" name="email" placeholder="Email" />
          <input type="password" name="password" placeholder="Password" />
          <button type="submit">Login</button>
        </form>
      );
    },

然后，您可以使用FormData来解析表单(如果需要的话，还可以从其条目构造一个JSON对象)。

handleLogin: function(e) {
   const formData = new FormData(e.target)
   const user = {}

   e.preventDefault()

   for (let entry of formData.entries()) {
       user[entry[0]] = entry[1]
   }

   // Do what you will with the user object here
}

es6析构的更清晰的例子

class Form extends Component {
    constructor(props) {
        super(props);
        this.state = {
            login: null,
            password: null,
            email: null
        }
    }

    onChange(e) {
        this.setState({
            [e.target.name]: e.target.value
        })
    }

    onSubmit(e) {
        e.preventDefault();
        let login = this.state.login;
        let password = this.state.password;
        // etc
    }

    render() {
        return (
            <form onSubmit={this.onSubmit.bind(this)}>
                <input type="text" name="login" onChange={this.onChange.bind(this)} />
                <input type="password" name="password" onChange={this.onChange.bind(this)} />
                <input type="email" name="email" onChange={this.onChange.bind(this)} />
                <button type="submit">Sign Up</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>
    )
  }
}

下面是我使用单个inputChangeHandler收集多个表单输入的方法

import React from "react";

const COLORS = ["red", "orange", "yellow", "purple", "green", "white", "black"];

export default function App() {

  const initialFormFields = {
    name: undefined,
    email: undefined,
    favourite_color: undefined
  };
  const [formInput, setFormInput] = React.useState(initialFormFields);

  function inputChangeHandler(event) {
    setFormInput(prevFormState => ({
      ...prevFormState,
      [event.target.name]: event.target.value
    }))
  };

  return (
    <div className="App">
      <form>
        <label>Name: <input name="name" type="text" value={formInput.name} onChange={inputChangeHandler}/></label>
        <label>Email: <input name="email" type="email" value={formInput.email} onChange={inputChangeHandler}/></label>
        <div>
          {COLORS.map(color => <label><input type="radio" name="favourite_color" value={color} key={color} onChange={inputChangeHandler}/> {color} </label>)}
        </div>
      </form>

      <div>
        Entered Name: {formInput.name}
        Entered Email: {formInput.email}
        Favourite Color: {formInput.favourite_color}
      </div>
    </div>
  );
}

这可能会帮助Meteor (v1.3)的用户:

render: function() {
    return (
        <form onSubmit={this.submitForm.bind(this)}>
            <input type="text" ref="email" placeholder="Email" />
            <input type="password" ref="password" placeholder="Password" />
            <button type="submit">Login</button>
        </form>
    );
},
submitForm: function(e) {
    e.preventDefault();
    console.log( this.refs.email.value );
    console.log( this.refs.password.value );
}

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>
)

}