adding-to-redux-form-fieldarray-1.js

<form onSubmit={handleSubmit}>
  <Field
    name="firstname"
    component={customInput}
    type="text"
    label="First Name"
    validate={[required]}
    normalize={capitalize}
  />

  <FieldArray name="discountCodes" component={discounts} />

  <button type="submit">Submit</button>
</form>

export const discounts = ({ fields }) => (
  <div className="custom-field-array-container">
    {fields.map((code, index) => (
      <div key={index} className="field-array-item">
        <Field
          name={code}
          type="text"
          component={customInput}
          label={`Discount Code #${index + 1}`}
          autoFocus
        />
        <button type="button" onClick={() => fields.remove(index)}>
          &times;
        </button>
      </div>
    ))}
    <button type="button" onClick={() => fields.push()}>
      Add {!fields.length ? "Discount Code(s)" : "Another Discount Code"}
    </button>
  </div>
);