Utilizing a C# backend, I decided to incorporate a C# principle into the Angular frontend. Here is what I came up with:
declare interface Date {
addDays(days: number): Date;
addYears(years: number): Date;
isToday(): boolean;
isSameDate(date: Date): boolean;
customFormat(): string;
}
declare interface String {
ToDate(): Date;
}
declare interface Array<T> {
ToDate(): string[];
}
Array.prototype.ToDate = function (): string[] {
return this.valueOf().map(timestamp => timestamp.ToDate());
};
String.prototype.ToDate = function (): Date {
return new Date(this.valueOf());
};
Date.prototype.addDays = function (days: number): Date {
if (!days) return this;
let date = new Date(this.valueOf());
date.setDate(date.getDate() + days);
return date;
};
Date.prototype.addYears = function (years: number): Date {
if (!years) return this;
let date = new Date(this.valueOf());
date.setFullYear(date.getFullYear() + years);
return date;
};
Date.prototype.isToday = function (): boolean {
let today = new Date();
return this.isSameDate(today);
};
Date.prototype.isSameDate = function (date: Date): boolean {
return date && this.getFullYear() === date.getFullYear() && this.getMonth() === date.getMonth() && this.getDate() === date.getDate();
};
Date.prototype.customFormat = function (): string {
let date = new Date(this.valueOf());
let yyyy = date.getFullYear();
let mm = date.getMonth() + 1;
let dd = date.getDate();
return dd + "/" + mm + "/" + yyyy;
};
The concept behind this approach is that it allows actions like
let foo = new Date();
foo.addYears(10);
This mimics how extensions work in C#. However, the issue arises when these prototype extensions seem to vanish once in production.
Attempting to declare everything globally by doing this:
export {};
declare global {
interface Date {
addDays(days: number): Date;
addYears(years: number): Date;
isToday(): boolean;
isSameDate(date: Date): boolean;
customFormat(): string;
}
}
declare global {
interface String {
ToDate(): Date;
}
}
declare global {
interface Array<T> {
ToDate(): string[];
}
}
// and so on
did not yield any results.
I also experimented with importing the file "date.extensions.ts" in the index.html within a script tag, but it still did not function correctly.
Furthermore, I referred to this resource, however, I am uncertain about where to include the import statement in the final step of the solution.
How can I ensure that the extensions perform as intended?