Mega Code Archive

 

Categories / Delphi / Strings

 

How to check a String for a Valid Email Address

Title: How to check a String for a Valid Email Address function MailURLMayBeInvalid(const s: string): Boolean; var i: Integer; c: string; begin // ' ', ?, ?, ¨¹, ?, [, ], (, ), : in EMail-Address Result := (Trim(s) = '') or (Pos(' ', AnsiLowerCase(s)) 0) or (Pos('?', AnsiLowerCase(s)) 0) or (Pos('?', AnsiLowerCase(s)) 0) or (Pos('¨¹', AnsiLowerCase(s)) 0) or (Pos('?', AnsiLowerCase(s)) 0) or (Pos('[', AnsiLowerCase(s)) 0) or (Pos(']', AnsiLowerCase(s)) 0) or (Pos('(', AnsiLowerCase(s)) 0) or (Pos(')', AnsiLowerCase(s)) 0) or (Pos(':', AnsiLowerCase(s)) 0); if Result then Exit; // @ not in EMail-Address; i := Pos('@', s); Result := (i = 0) or (i = 1) or (i = Length(s)); if Result then Exit; Result := (Pos('@', Copy(s, i + 1, Length(s) - 1)) 0); if Result then Exit; // Domain c := Copy(s, i + 1, Length(s)); Result := Length(c) = 1; if Result then Exit; i := Pos('.', c); Result := (i = 0) or (i = 1) or (i = Length(c)); end;