How to compare 2 dates using directive.

In Angular, you can compare two dates using a custom directive. Here’s a basic example of how you can achieve this:

import { Directive, Input } from '@angular/core';
import { NG_VALIDATORS, Validator, AbstractControl } from '@angular/forms';

@Directive({
  selector: '[appCompareDates]',
  providers: [{provide: NG_VALIDATORS, useExisting: CompareDatesDirective, multi: true}]
})
export class CompareDatesDirective implements Validator {
  @Input('appCompareDates') dateToCompare: Date;

  validate(control: AbstractControl): {[key: string]: any} | null {
    const controlDate = new Date(control.value);
    if (controlDate && this.dateToCompare && controlDate > this.dateToCompare) {
      return {'dateInvalid': true};
    }
    return null;
  }
}

 

In this example, the appCompareDates directive is used to compare the date from the control it’s applied to with another date (dateToCompare). If the control’s date is later than dateToCompare, it returns an error.

You can use this directive in your HTML like this:

 

 

In this case, date1 is the date you want to validate, and date2 is the date you’re comparing it to1.

Please note that this is a simple example and might need to be adjusted based on your specific requirements. For instance, you might want to add checks for whether the dates are defined, or handle different date formats12. Also, remember to declare and import the directive in your module file.

Thanks