Angular 10 References/ Forms
References

[pattern] validation directive

A directive that adds regex pattern validation to controls marked with the pattern attribute. The regex must match the entire control value.

The directive is provided with the NG_VALIDATORS multi-provider list.

Adding a pattern validator

The following example shows how to add a pattern validator to an input attached to an ngModel binding.

<input name="firstName" ngModel pattern="[a-zA-Z ]*">