C#獲得明天，後天，昨天，前天等日期

DateTime dt = DateTime.Now;
dt.AddDays(-1);//-1為昨天

那麼後天為

dt.AddDays(2);

如下:
 

//如果是當天或則是昨天發布的,就給出new.gif的小表徵圖提示                         if (ds.Tables[0].Rows[i]["T_Notice_Date"].ToString() != "")                         {                             DateTime _date = new DateTime();                             _date = DateTime.Parse(ds.Tables[0].Rows[i]["T_Notice_Date"].ToString()).Date;                             if (_date.Equals(DateTime.Today) || _date.Equals(DateTime.Today.AddDays(-1)))                             {                                 _str.Append("<img alt=\"\" src=\"images/new.gif\" />");                             }                         }