判断，字符为汉字，数字

function IsNumber(const s: string): Boolean;
var
  i: Integer;
begin
  if IsEmpty(s) or not (Pos('-', s) in[0, 1]) then
  begin
    Result := False;
    Exit;
  end;
  Result := True;
  for i := 1 to Length(s) do //Not empty:
    if not (s[i] in ['0'..'9', '.', '-']) then
    begin
      Result := False;
      Break;
    end;
end;

function IsAlpha(const s: string): Boolean;
var
  i: Integer;
begin
  Result := False;
  for i := 1 to Length(s) do
    if s[i] in ['A'..'Z', 'a'..'z'] then
    begin
      Result := True;
      Break;
    end;
end;

function IsAllAlpha(const s: string): Boolean;
var
  i: Integer;
begin
  Result := True;
  for i := 1 to Length(s) do
    if not (s[i] in ['A'..'Z', 'a'..'z']) then
    begin
      Result := False;
      Break;
    end;
end;