React 原生Form的使用

Text

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

    this.handleChange = this.handleChange.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleChange(event) {
    this.setState({value: event.target.value});
  }

  handleSubmit(event) {
    alert('A name was submitted: ' + this.state.value);
    event.preventDefault();
  }

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        <label>
          Name:
          <input type="text" value={this.state.value} onChange={this.handleChange} />
        </label>
        <input type="submit" value="Submit" />
      </form>
    );
  }
}

TextArea

class EssayForm extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      value: 'Please write an essay about your favorite DOM element.'
    };

    this.handleChange = this.handleChange.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleChange(event) {
    this.setState({value: event.target.value});
  }

  handleSubmit(event) {
    alert('An essay was submitted: ' + this.state.value);
    event.preventDefault();
  }

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        <label>
          Essay:
          <textarea value={this.state.value} onChange={this.handleChange} />
        </label>
        <input type="submit" value="Submit" />
      </form>
    );
  }
}

Select

class FlavorForm extends React.Component {
  constructor(props) {
    super(props);
    this.state = {value: 'coconut'};

    this.handleChange = this.handleChange.bind(this);
    this.handleSubmit = this.handleSubmit.bind(this);
  }

  handleChange(event) {
    this.setState({value: event.target.value});
  }

  handleSubmit(event) {
    alert('Your favorite flavor is: ' + this.state.value);
    event.preventDefault();
  }

  render() {
    return (
      <form onSubmit={this.handleSubmit}>
        <label>
          Pick your favorite flavor:
          <select value={this.state.value} onChange={this.handleChange}>
            <option value="grapefruit">Grapefruit</option>
            <option value="lime">Lime</option>
            <option value="coconut">Coconut</option>
            <option value="mango">Mango</option>
          </select>
        </label>
        <input type="submit" value="Submit" />
      </form>
    );
  }
}

Multiple Inputs

class Reservation extends React.Component {
  constructor(props) {
    super(props);
    this.state = {
      isGoing: true,
      numberOfGuests: 2
    };

    this.handleInputChange = this.handleInputChange.bind(this);
  }

  handleInputChange(event) {
    const target = event.target;
    const value = target.type === 'checkbox' ? target.checked : target.value;
    const name = target.name;

    this.setState({
      [name]: value
    });
  }

  render() {
    return (
      <form>
        <label>
          Is going:
          <input
            name="isGoing"
            type="checkbox"
            checked={this.state.isGoing}
            onChange={this.handleInputChange} />
        </label>
        <br />
        <label>
          Number of guests:
          <input
            name="numberOfGuests"
            type="number"
            value={this.state.numberOfGuests}
            onChange={this.handleInputChange} />
        </label>
      </form>
    );
  }
}

Radio

import React, { Component } from "react";

class Demo2 extends Component {
  constructor() {
    super();
    this.state = {
      name: "React"
    };
    this.onValueChange = this.onValueChange.bind(this);
    this.formSubmit = this.formSubmit.bind(this);
  }

  onValueChange(event) {
    this.setState({
      selectedOption: event.target.value
    });
  }

  formSubmit(event) {
    event.preventDefault();
    console.log(this.state.selectedOption)
  }

  render() {
    return (
      <form onSubmit={this.formSubmit}>
        <div className="radio">
          <label>
            <input
              type="radio"
              value="Male"
              checked={this.state.selectedOption === "Male"}
              onChange={this.onValueChange}
            />
            Male
          </label>
        </div>
        <div className="radio">
          <label>
            <input
              type="radio"
              value="Female"
              checked={this.state.selectedOption === "Female"}
              onChange={this.onValueChange}
            />
            Female
          </label>
        </div>
        <div className="radio">
          <label>
            <input
              type="radio"
              value="Other"
              checked={this.state.selectedOption === "Other"}
              onChange={this.onValueChange}
            />
            Other
          </label>
        </div>
        <div>
          Selected option is : {this.state.selectedOption}
        </div>
        <button className="btn btn-default" type="submit">
          Submit
        </button>
      </form>
    );
  }
}

export default Demo2;