usernamePattern top-level property
Username regex
Implementation
final RegExp usernamePattern = RegExp(
r'^[a-zA-Z0-9][a-zA-Z0-9_.]+[a-zA-Z0-9]$',
);
usernamePattern property
Username regex
final RegExp usernamePattern = RegExp(
r'^[a-zA-Z0-9][a-zA-Z0-9_.]+[a-zA-Z0-9]$',
);