Antd提供了DatePicker的自定义渲染功能，可用于添加自己的DOM元素。可以使用renderExtraFooter函数来添加按钮。要更改“现在”功能，可以使用renderExtraFooter函数并使用updateNow函数进行更改。

代码示例：

import React, { useState } from "react";
import { DatePicker } from "antd";

const App = () => {
  const [selectedDate, setSelectedDate] = useState(undefined);

  const onDatePickerChange = (dateValue) => {
    setSelectedDate(dateValue);
  };

  const disabledDate = (date) => {
    return date && date > new Date();
  };

  const renderExtraFooter = () => {
    return (
      <>
         setSelectedDate(new Date())}>Set Today
         setSelectedDate(undefined)}>Clear
      
    );
  };

  return (
    
  );
};

export default App;