小知识点记录笔记

1 System.IFormatProvider format = new System.Globalization.CultureInfo("zh-CN", true);
2 string str1 = "20140812";
3 string str2 = "20140812 16:41:30";
4 DateTime time1 = DateTime.ParseExact(str1, "yyyyMMdd", format);
5 DateTime time2 = DateTime.ParseExact(str2, "yyyyMMdd HH:mm:ss", format);

 1 private bool ParseDateTime(string cellValue, out string strDate)
 2 {
 3     DateTime date = default(DateTime);
 4     double value = default(double);
 5     if (double.TryParse(cellValue, out value))
 6     {
 7         strDate = DateTime.FromOADate(value).ToString("yyy-MM-dd HH:mm:ss");
 8     }
 9     else
10     {
11         if (DateTime.TryParse(cellValue, out date))
12         {
13             strDate = date.ToString("yyy-MM-dd HH:mm:ss");
14         }
15         else
16         {
17             strDate = string.Empty;
18         }
19     }
20     string reg = @"^(\d{4})-([0-1]\d)-([0-3]\d)\s([0-2]\d):([0-5]\d):([0-5]\d)$";
21     if (Regex.IsMatch(strDate, reg))
22     {
23         return true;
24     }
25     return false;
26 }