Avoiding Input Issues with MatDatepicker in Angular

When using the Angular Material Datepicker (MatDatepicker), developers often face formatting challenges, especially when dates are manually input by the user. The material-moment-adapter provides an elegant solution to handle these issues.

1. Date Format Issue During Manual Input

When using the MatDatepicker, if a user manually enters a date in the format dd/mm/yyyy (french format date) and the focus changes, the date might automatically be interpreted as the yyyy-dd-mm format. This unexpected transformation can lead to confusion and input errors. To address this behavior, we can configure a custom date format with MomentDateAdapter.

2. Timezone Conversion Issues with GMT +1

Another common issue faced is when the date 12/06/2023 00:00:00 becomes 11/06/2023 23:00:00 due to GMT +1 timezone conversion. This unintended shift can cause confusion and inaccuracies.

The solution is to utilize the useUtc: true option provided by the material-moment-adapter. When this option is set to true, dates won’t undergo undesired timezone adjustments.

Implementation Guide

Install the necessary dependencies:

npm install @angular/material-moment-adapter moment

In your module configuration, import the necessary modules and provide custom date format:

`import { MomentDateAdapter, MAT_MOMENT_DATE_ADAPTER_OPTIONS } from '@angular/material-moment-adapter';

export const CUSTOM_DATE_FORMAT = {
parse: {
dateInput: 'DD/MM/YYYY',
},
display: {
dateInput: 'DD/MM/YYYY',
monthYearLabel: 'MMMM YYYY',
dateA11yLabel: 'DD/MM/YYYY',
monthYearA11yLabel: 'MMMM YYYY',
},
};

@NgModule({
...
providers: [
{ provide: MAT_DATE_LOCALE, useValue: 'fr-FR' },
{ provide: MAT_DATE_FORMATS, useValue: CUSTOM_DATE_FORMAT },
{ provide: DateAdapter, useClass: MomentDateAdapter },
{ provide: MAT_MOMENT_DATE_ADAPTER_OPTIONS, useValue: { useUtc: true } },
],
...
})`

With the above configuration, MatDatepicker will now correctly interpret manually entered dates and avoid unwanted timezone transformations.

Conclusion

The Angular Material Datepicker is a versatile component, but it’s essential to handle date formatting and timezone issues for a seamless user experience. By leveraging material-moment-adapter and the configurations outlined above, developers can ensure consistent and accurate date input and display.