function StrArrayJoin(const StringArray : array of string; const Separator : string) : string;
var
  i : Integer;
begin
  Result := '';
  for i := low(StringArray) to high(StringArray) do
    Result := Result + StringArray[i] + Separator;

  Delete(Result,Length(Result),1);
end;

只需遍历阵列并与分离器连接即可.

还有一个小测试例子：

procedure TForm1.FormCreate(Sender: TObject);
begin
  Caption :=StrArrayJoin(['This','is','a','test'],' ');
end;