email pattern validation in angular 8 code example

Example 1: angular email regular expression

validateEmail(email) {
 const regularExpression = /^(([^<>()\[\]\\.,;:\s@"]+(\.[^<>()\[\]\\.,;:\s@"]+)*)|(".+"))@((\[[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\])|(([a-zA-Z\-0-9]+\.)+[a-zA-Z]{2,}))$/;
 return regularExpression.test(String(email).toLowerCase());
}

Example 2: email pattern in html input angular

<input name="officialEmail" [ngModel]="user.officialEmail" required [pattern]="emailPattern" #offEmail="ngModel">