DateTime dt_test;
string s_test;
s_test  ="2005-06-01";
dt_test = Convert.ToDateTime(s_test);
Console.WriteLine(dt_test.ToString()); // 2005-6-1 0:00:00
Console.WriteLine(dt_test.ToShortDateString());//2005-6-1 请问怎样实现输出, 2005-06-01(长日期格式,必须保证8位).