我在渲染函数中有一个简单的表单,如下所示:

render : function() {
      return (
        <form>
          <input type="text" name="email" placeholder="Email" />
          <input type="password" name="password" placeholder="Password" />
          <button type="button" onClick={this.handleLogin}>Login</button>
        </form>
      );
    },
handleLogin: function() {
   //How to access email and password here ?
}

我应该在我的handleLogin: function(){…}访问电子邮件和密码字段?


当前回答

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>
        )
    }

}

其他回答

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 );
}

如果元素名多次出现,则必须使用forEach()。

html

  <input type="checkbox" name="delete" id="flizzit" />
  <input type="checkbox" name="delete" id="floo" />
  <input type="checkbox" name="delete" id="flum" />
  <input type="submit" value="Save"  onClick={evt => saveAction(evt)}></input>

js

const submitAction = (evt) => {
  evt.preventDefault();
  const dels = evt.target.parentElement.delete;
  const deleted = [];
  dels.forEach((d) => { if (d.checked) deleted.push(d.id); });
  window.alert(deleted.length);
};

注意,本例中的dels是RadioNodeList,而不是数组,也不是Iterable。forEach()是列表类的内置方法。这里不能使用map()或reduce()。

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>
  );
}

迈克尔·肖克的回答是:

class MyForm extends React.Component {
  constructor() {
    super();
    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleSubmit(event) {
    event.preventDefault();
    const data = new FormData(event.target);

    console.log(data.get('email')); // reference by form input's `name` tag

    fetch('/api/form-submit-url', {
      method: 'POST',
      body: data,
    });
  }

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        <label htmlFor="username">Enter username</label>
        <input id="username" name="username" type="text" />

        <label htmlFor="email">Enter your email</label>
        <input id="email" name="email" type="email" />

        <label htmlFor="birthdate">Enter your birth date</label>
        <input id="birthdate" name="birthdate" type="text" />

        <button>Send data!</button>
      </form>
    );
  }
}

参见这篇Medium文章:如何用Just React处理表单

此方法仅在按下提交按钮时获取表单数据。我觉得干净多了!

我认为这也是你需要的答案。此外,我在这里添加了所需的属性。每个输入组件都是函数。你需要在这里加入你自己的逻辑。

handleEmailChange: function(e) {
    this.setState({email: e.target.value});
},
handlePasswordChange: function(e) {
   this.setState({password: e.target.value});
},
formSubmit : async function(e) {
    e.preventDefault();
    // Form submit Logic
  },
render : function() {
      return (
        <form onSubmit={(e) => this.formSubmit(e)}>
          <input type="text" name="email" placeholder="Email" value={this.state.email} onChange={this.handleEmailChange} required />
          <input type="password" name="password" placeholder="Password" value={this.state.password} onChange={this.handlePasswordChange} required />
          <button type="button">Login</button>
        </form>);
},
handleLogin: function() {
    //Login Function
}