DateRangeField.js

class DateRangeField extends Component {
  state = {
    focusedInput: null,
  }

  handleCorrectInput = e => {
    // some additional staff

    switch (keyButton) {
      case 42:
        // some additional staff
        return
      default:
        // some additional staff
        this.handleValidationInput(e)
    }
  }

  /**
   * Что скажете по поводу этой функции валидации редакс формы?
   */
  handleValidationInput = e => {
    const name = e.target.id.indexOf('start') !== -1 ? 'Start Date' : 'Finish Date'
    const value = e.target.value

    if (!/\d{2}\/\d{2}\/\d{4}/.test(value)) {
      this.props.meta.touched = true
      this.props.meta.error = { startDate: `${name}: Format must be MM/DD/YYYY` }
    } else if (parseInt(value.substr(0, 2)) > 12) {
      // some additional staff
    } else {
      this.props.meta.touched = false
    }
  }

  render(){return null}
}