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