[Angular] Custom a DatePipe to support special time zone conversion from user

Background

It didn't use a time zone format of datetime in database, data has only one time zone.

a. Columns:

b. Data:

So I'll define a custom DatePipe to extend DatePipe in my source code of Angular.

How to implement?

1. Create a pipe class of Angular called MyDatePipe.

复制代码
Output format: { yyyy/MM/dd HH:mm:ss }
javascript 复制代码
import { DatePipe } from '@angular/common';
import { Pipe, PipeTransform } from '@angular/core';
@Pipe({
  name: 'myDate',
  standalone: true
})
export class MyDatePipe extends DatePipe implements PipeTransform {
  override transform(value: any, args?: any): any {
    let myDate = new Date(value);
    myDate.setHours(myDate.getHours() + args);
    return super.transform(myDate, 'yyyy/MM/dd HH:mm:ss');
  }
}

2. Using it in your component

a. Component

providers: [MyDatePipe],

imports: [MyDatePipe]

javascript 复制代码
import { Component, OnInit, ChangeDetectionStrategy } from '@angular/core';
import { FormsModule } from '@angular/forms';

import { TokenKey, TokenPre } from '@app/config/constant';
import { WindowService } from '@app/core/services/common/window.service';
import { NzButtonModule } from 'ng-zorro-antd/button';
import { NzInputModule } from 'ng-zorro-antd/input';

import { MyDatePipe } from '../../pipes/my-datepipe';

@Component({
  selector: 'app-pages-empty',
  templateUrl: './empty.component.html',
  changeDetection: ChangeDetectionStrategy.OnPush,
  standalone: true,
  providers: [MyDatePipe],
  imports: [NzButtonModule, NzInputModule, FormsModule, MyDatePipe]
})
export class EmptyComponent implements OnInit {
  token?: string;
  srvDate: Date = new Date();
  srvOffsetOfTimeZone: number = 8; // offset of server time zone
  userOffsetOfTimeZone: number = -5.5; // offset of user time zone

  constructor(private windowServe: WindowService, private myDatePipe: MyDatePipe) {}

  ngOnInit(): void {}

  setToken(): void {
    this.windowServe.setSessionStorage(TokenKey, TokenPre + this.token);
  }

  getDate(): void {
    this.srvDate = new Date();
    const userDate = this.myDatePipe.transform(this.srvDate, -this.srvOffsetOfTimeZone + this.userOffsetOfTimeZone);
    console.log(`User date: ${userDate}`);
  }
}

b. Html

javascript 复制代码
<button nz-button (click)="getDate()">Show user date</button>
Server time(UTC {{ srvOffsetOfTimeZone }}):{{ srvDate }}
<br />

UTC time(UTC): {{ srvDate | myDate : -srvOffsetOfTimeZone }}
<br />
User time(UTC {{ userOffsetOfTimeZone }}):{{ srvDate | myDate : -srvOffsetOfTimeZone + userOffsetOfTimeZone }}

3. Test result

相关推荐
mCell17 小时前
GSAP ScrollTrigger 详解
前端·javascript·动效
gnip17 小时前
Node.js 子进程:child_process
前端·javascript
excel20 小时前
为什么在 Three.js 中平面能产生“起伏效果”?
前端
excel21 小时前
Node.js 断言与测试框架示例对比
前端
天蓝色的鱼鱼1 天前
前端开发者的组件设计之痛:为什么我的组件总是难以维护?
前端·react.js
codingandsleeping1 天前
使用orval自动拉取swagger文档并生成ts接口
前端·javascript
石金龙1 天前
[译] Composition in CSS
前端·css
白水清风1 天前
微前端学习记录(qiankun、wujie、micro-app)
前端·javascript·前端工程化
Ticnix1 天前
函数封装实现Echarts多表渲染/叠加渲染
前端·echarts
用户22152044278001 天前
new、原型和原型链浅析
前端·javascript