Prevent those double clicks in React

loading.jsx

React.creatClass({
  render() {
    return (
      <form onSubmit={handleSubmit}>
        <input
          type="submit"
          value={this.state.loading ? "Doing it..." : "Do it!"}
          disabled={this.state.loading}
          />
      </form>
    )
  },
  
  handleSubmit() {
    this.setState({ loading: true })
  }
})