Add local plugin to dayjs.

dayjs-extend.md

Add local plugin to dayjs.

// dayjs.ext.ts

import dayjs from 'dayjs';

declare module 'dayjs' {
  interface Dayjs {
    toISODate(): string;
  }
}

const plugin = (_option: any, dayjsClass: any, _dayjsFactory: any) => {
  const proto = dayjsClass.prototype;
  proto.toISODate = function (): string {
    return this.format('YYYY-MM-DD');
  };
};

dayjs.extend(plugin);

Import dayjs.ext.ts at main.ts(Angular) to apply.

// main.ts

import './app/utils/dayjs.ext'

Reference

• https://kakkoyakakko2.hatenablog.com/entry/2018/06/28/003000
• https://day.js.org/docs/en/plugin/plugin